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FAQs on Storing Synthetic Seawater

Related Articles: Synthetic or Natural Seawater, Saltwater Impressions (Synthetics Review) By Steven Pro, Specific Gravity,  Water Changes/ChangingpH, Alkalinity, Marine Alkalinity

Related FAQs: Seawater 1, Seawater 2, Seawater 3, Seawater 4, Seawater 5, Seawater 6, & FAQs on Mixing, Supplementing, Moving, Physical/Chemical Troubleshooting/Fixing... By Make/Manufacturer: Natural Seawater. Synthetics: Aquarium Systems (Instant Ocean, Reef Crystals), Aquacraft (Marine Environments, BioSea...), Central Garden (Oceanic), Kent Marine (SeaSalt), Red Sea (Red Sea Salt, Coral Pro Salt), SeaChem Marine (Marine Salt, Reef Salt), Energy Savers (Coralife), Tropic Marin, Other Brands... About Buying Pre-mixed Seawater, About  Synthetics Manufacturers Advertising Claims...  Spg 1, Treating Tapwater For Marine Aquarium Use, Reverse Osmosis Filtration 

Do synthetic salt mixes meet all sorts of marine lives' needs? Do they become toxic with age, storage?

Premixed Saltwater Storage  3/26/14
Hi Guys
I’m looking at storing about 100 gallons of premixed saltwater for small but constant water changes (about 3 gallons / day) throughout the month, essentially taking advantage of my Profilux controller. This water would be fed from the storage container into my sump.
The container would need to be stored outside in direct sunlight, where the afternoon temperature can reach 34˚C ( Phuket ). Should I be concerned that the heat will render the ASW unusable or unsafe and would storing the ASW in dark containers be beneficial?
<I wouldn't be concerned re the heat itself; nor would I use dark/ened containers... likely to make it even hotter!>
I’m not sure if its worth noting but I use SeaChem Reef Salt out of convenience. We’re slightly limited on what's available over here ….
Thanks again
<The water will be fine... Wish we were in Myanmar diving... Oh, am on the way to Cozumel right now with my sister to do just that! Cheers, Bob Fenner>
Re: Premixed Saltwater Storage  3/27/14

Oh how I envy you … It would be great to see you in the LOS one day!
Would you run a powerhead 24/7 to circulate the water or just turn it over every few days,
<Ah yes; please read here: http://wetwebmedia.com/seah2ostoring.htm
and look through the linked files above>
and what's is your recommendation over SeaChem’s Reef Salt or Reef Crystals from France?
<Both products made by AS... I have a slight preference for the SeaChem>
Thanks again
<Ah, welcome. BobF>

Moving live sand; synthetic salt mix, stored water f's as well    7/1/13
Hello WWM Crew,
  First off, a big Thank-You for all the experience you share on this labour of love website. I have learned so much in the last few years reading FAQ’s on this site and R. Fenner’s book (which I have an autographed copy). It’s amazing how much is on this site. I search for an answer for one question and then I just get lost in reading all the info on my question. I have a couple of questions, one I know I have read on this site before but for the life of me I can’t remember the response and I just can’t find it again. When I take the cover off of my 20g trash can of new salt water that has been aerating for a week I get a faint smell of ammonia (like a cat litter box) but just for a split second. I test the water for ammonia and of course I get a 0. What is the cause of this?
<I suspect (don't know) that you are actually detecting "faint ammonia" from the small bit of organic material that is part of most commercial salt mixes... being liberated as a gas by mainly chemical decomposition. Not to be mysterious, the most common salt in synthetics (NaCl) is to degrees simple "sea salt" collected from insolation ponds...>
 My next question is about mixing salt brands. I always use Tropic Marin salt and I received a bucket of Red Sea Coral Pro for free. Would I see any negative effects on my system if I were to mix 80% Tropic Marin and 20% Red Sea when I mix up my ro/di water in my 20g trash can?
<Perhaps a little; not dangerous>
Now for my dilemma(it’s going to be long). I am going to be moving to a new house and I am reading quite a few articles on moving and disturbing live sand. Most opinions are that it is not worth the trouble using the same live sand as most everything will die off and cause more pollution and re cycling of the new set up. I also read that it is a good idea to change the sand every few years as the sand loses buffering capacity over the years. The sand I have now is about 6 years old. Would you give me your thoughts on my moving plan?
<I might save, use a "bit" of the old sand (transported in an insulated container... an inch or two water over it) on top of the new substrate. I'd likely rinse, keep the remainder of the olde sand for possible future "other" use/s>
First I have the luxury of time on my side. The new house is only 20 minutes away and will be empty on August, 1st and I will be in the old house till September, 1st. So you see I want to plan it properly. Here is my idea. First I will take 20g of water from the DT(90g)and set it up in my 20g long with about 20lbs of LR and some sand. The 20g long will also have a canister filter running with a Polyfilter, Purigen and some filter floss. I will put my Aqua C Remora on it as well as a power head and a T5 strip light. Then I plan to put my live stock in the 20g long which consists of 1 Percula, 1 Royal Gramma, 1 Pajama Cardinal, 1 Brittle star, 1 Cleaner Shrimp and various snails. The rest of the LR and LS(about 80 lbs each)I will put in a Rubbermaid tub with a heater, power head and my Vertex 100 skimmer. I will also take all of my water from the 90g to the new house. Now that the 90g is empty I will take the opportunity to have it drilled as I have been using a CPR siphon overflow for the last 6 years and I have to say, believe or not, I have had absolutely no problems with it. When I get the tank to the new house I will add the water and LR from the old house and start up the system. If I move the LR to the new house in the Rubbermaid tub do you think there will be any die off?
<Not much>
Now comes the part about the sand. Would it be better just to use new LS about 1” depth and add some of the old LS to seed?
<Yes; but more of the new>
 After all that I will run the tank for August and bring the live stock when parameters are all good. How long would it be safe to keep the live stock in the 20g long set up?
<As long as they get along; indefinitely>
 Well I think that is my whole plan. Any thoughts or ideas would be welcome as I would like this move to go as smooth as possible, I know you understand that. I am sorry for this long letter but this is the first time I am doing a move with an aquarium and I would like to avoid any disasters if I can. Thanks in advance for your expertise.
<I might speed up the transit, resetting up time frame myself. But what you've stated will work. Bob Fenner>

Tupperware vs. glass     6/25/13
Hi crew! This is becoming habit forming, talking with you ! But it's a good habit!
Here's an easy one for ya, and the answer is probably just a matter of opinion, but I respect your opinions, so here goes!
I have a 30 gallon tank,.. I NEED a container to store water in for changes. I have always bought Tupperware for this purpose, but how about a spare tank?
Is this a bad idea? Too much light?
<Ahh, both would work fine... Nice to have the tank around... just in case.
And am a huge fan of Rubbermaid Brute trash cans>
There, see, I told ya it was easy! Hmmm, maybe a bit dumb?
Hope not!
<And you, B>
Re: Tupperware vs. glass     6/26/13
Thanks Bob, I knew I could count on you to be, oh so diplomatic!
The Rubbermaid Brute trash cans look nice and strong, but I would love a square one, as it fits better into my decor! LOL!
<They do have some great troughs...>
Have to see if one is out there!
Thanks for your expert advice ;)
<Ah, welcome. B>

preparing used container for saltwater use - 01/27/2013
Greetings!  I've purchased a few plastic 55 gallon containers that were commercially used for a drink mix containing rum, propylene glycol, and ethanol.  I want to use them to make and store new saltwater for my reef tank (contains SPS, LPS).  What is the best way to clean them before I put them to use?
I've read that a diluted bleach solution with a lot of rinsing would work, but bleach sounds scary...  Is it safe?
<Yes... rinsed a few times, the tanks refilled, treated w/ an overdose of dechlorinating product>
I appreciate the help!  Thanks!
<Welcome. Bob Fenner> 

Water stinks! New water make-up      7/8/12
I have an RO/DI unit for water. I mix in a Brute trash can, as recommended. I raise the temperature to about 75F during mixing, use power jets to agitate, and generally age the water a bit. My water tends stink (light mildew odor?),
<Can't say, but I'd likely be adding a good carbon filter here... If this doesn't do it, bleaching the whole apparatus occasionally>
and also has marine buffer precipitate (per the packaging, this could indicate "poor ionic balance").
Recently I left a full vat of water (with salt mix) for 2 days without aeration or heat. I thought I'd save some power, as I was not due for another water change for a week. After I noticed a much stronger stink, and for 4 days have used power jets/heater but the odor has not diminished (and the precipitate is far worse than normal).
<Summat growing there it seems>
Testing yields 7.9 ph and no measurable ammonia/nitrite/nitrate/phosphate.
Do I have anything to worry about in using this water?
<Not likely>
Could mildew or "poor ionic balance" cause a problem in the main tank?
<Some small chance of both, yes... I would be investigating what the source of both troubles are and fixing. For the latter, review the use of alkaline earth materials (additions of Ca, Mg...) and their counter effects on alkalinity/pH. You're likely fighting yourself here. Bob Fenner>
Re: Water stinks! Premix syn. and water qual. f's    7/11/12

Thank you. I noticed a fresh batch of RO water in a separate mixing vat, that had aged had no odor. I added salt, let it age, still no smell. It must have been the brute mixing vat I had been using.
<Rubbermaid "Brute" brand? Never had an issue w/ this fine line>
Likely from cooking live rock previously.
<Ahh! Assuredly this will do it>

This confirms for me that vinegar scrubs may not be adequate. And yes, I was fighting myself (what else is new).
<You are wise here: answer, "not much">
I filled it with water, added a 1300gph powerhead, a cup or so of bleach, and let it go for an hour plus. I then rinsed it three times.
What can I do to ensure any bleach residual is fully neutralized?
<Rinse, rock salt rinse of the polyethylene, air dry and/or sodium hypochlorite ("DeChlor" or such) dechlorinator use in spades... A week of air-drying will do it>
 I will add Seachem Prime to dechlorinate, but is that adequate?
<I'd let air dry, but enough of the Prime will be adequate... You can get/use simple "free chlorine" test kit/s... from the pool/spa outlets otherwise>
 I see this mitigates the chlorine, but there is discussion on the web that sodium hydroxide may remain?
<This is simple to rinse out. Cheers, Bob Fenner>
Re: Water stinks!   7/11/12

<Big J>
Oh the wars I wage on myself...What kind of chemistry nightmare have I caused...
<Heeee! Relative to what?>
Is it possible to ruin a brute trash can for water mixing purposes!?
<Not really; no... Our companies and many other petfish/ornamental aquatics, heck, institutions, put these durable products through use-hell... They really last and put up w/ abuse>
Well I see the air drying has at least eliminated all liquid. But, there is clouded precipitate left throughout the interior. It seems to be etched into the polyethylene. Perhaps a 24 hour vinegar soak and heavy scrubbing?
<I'd just leave the precipitate... not worry. BobF>

Salt Still OK?      6/15/12
To whom it may concern,
Thanks for taking the time to read this email.
I found a pale
<Pail, but now you've got me thinking re India Pale Ales...>
 of Kent salt mix in my basement the other day.  It is half used and has been sitting there for about a year. Is it still good to use or should I throw it out?
<It's fine... may take a while longer to dissolve... and I would pre-dissolve, store for a day or so ahead of use...>
Thanks for your time,
<Welcome. Bob Fenner> 
Re: Salt Still OK?      6/15/12

Thanks for your prompt reply!
<A pleasure. BobF>

premixed saltwater storage  10/5/09
Good afternoon,
<Good evening, Keith! JustinN here!>
I have a question regarding the storage of premixed saltwater. I currently use Red Sea Coral Pro salt and RO water. I use a Maxijet and a heater in a 6 gallon bucket. I mix the salt and let it mix with a powerhead and a heater and test ph, ca and Alk after 24 hours and the results are pH of 8.3, Ca of 440 and dKH of 8. I then cover the bucket with a lid and leave the heater and Maxijet on.
<Sounds good.>
When I remove the lid several days later I have noticed that my dKH goes up and my
Ca drops to about 360-380. I imagine this is kind of the same result as the night-day ph swing and that the Alk and Ca are working to stabilize pH?
<Mmm, more likely the stabilization of all things chemical in your water over time..>
Anyway, when it comes to water changes with this premixed water, what is the procedure? How long should I leave the water with the lid off before attempting a change?
<If you're circulating the air for 24+ hours with an air pump, you should be ready to go. Just perform a water change as normal.>
Should I add an airstone a couple of hours before the water change or does this sound like an unstable salt mix?
<More air never hurts, but I doubt its necessity. No personal experience with Red Sea's salt, but I doubt that the mix is a problem.>
I had just recently noticed coralline die off and lower Ca or more than usual ca consumption in my display tank that had been dead on for well over a year as well as lower pH overall (8.1) during the day.
<Coralline die-off and higher Ca usage would seem to be somewhat in conflict -- are there corals/clams that could be sapping the Ca from the water at a greater rate over time?>
This salt brand had been pretty much consistent for me since I started my tank, with no new livestock additions or equipment but to be quite honest I had never tested the bucket after the initial tests were satisfied after the mixing and aerating 24 hours later.
<Worthwhile to chart out results for a few sets of make-up water here, make sure there's not a trend of instability.>
Any insight or help would be greatly appreciated.
<On paper, I would say you appear to have everything right as needed. Have a look at my article on exactly this topic:
http://wetwebmedia.com/ca/volume_4/V4I2/Water_Makeup/makeup_water.htm --
you will find that your overall strategy fits the concepts laid out there pretty well to a T. Let us know if you have any more questions! -JustinN>

Re: premixed saltwater storage... & disc. of mixes, IO and Red Sea 
Thanks Justin.
I read the water change article, and it looked familiar, so it might have been where I initially got some of the practices I use now. I always do let the water age for at least a day, so stuff can become known before it's in the tank and too late.
I usually test too but so many buckets of the Red Sea had been dead on I kind of slacked on this last one until a WC had been done.
<Understandable -- when you get that rhythm, sometimes the lackadaisical attitude sets in... I know I'm guilty more than once!>
While I was waiting for your reply, I mixed up 2 other buckets of water, another of Red Sea Coral Pro and one of good ol' Instant Ocean just to make sure my test kits weren't out of whack. The Instant Ocean at SG of 1.026 was right on, Alk of 10, calcium of 380 and ph of 8.2-8.3. The second batch of Red Sea had an Alk of well over 14, but I stopped there because those drop tests run out pretty quick and I was yet unsure where the salt was going to be reading the next day. The Ca was at 440 and ph of 8.3 <I never trust my initial readings when mixing salt, and tend to only go on Salinity personally -- until the water has had some time to mix and stabilize.>
Like I said in my last email, I had used this brand of salt for over a year without issue, switching from Instant Ocean on the "advice" of other reefers when I started adding corals because of the low Ca in IO.
<Understood -- plenty of reefers have great success with this salt -- I doubt the salt itself is really an issue.>
A little background on my tank. I have a 20 gal long tank. It has 24 lbs of aragonite sand, about 20 lbs of liverock and has 2 150 gal powerheads on opposite sides. I also use an Aquaclear 70 that is 300 gph for flow and occasionally Chemipure since my skimmer started to leak and it had to be removed about 6 months ago.
<Sounds good -- do make sure to clean out any filter media in the Aquaclear regularly here.>
I do 2 5% WCs weekly or at least 1 10%. The tank is lit by 130 watts of PC, 1 1000k and 1 actinic. I have 2 false Perculas, a watchman and his pistol shrimp buddy, a cleaner shrimp, 4 blue leg hermits and 4 Astrea snails. For corals I have Xenia, mushrooms, zoos and 2 LPS corals: a torch coral and a candy cane.
<Sounds very nice.>
I have had these corals doing well and growing now since Feb of this year (that is when the final ones were
added) I have great coralline too, but everywhere I read that to sustain coralline you needed a higher Ca, like in the 400-450 range in a captive system...which with the addition of the LPs is why I opted to try out a "reef" salt in the first place....but as you can see, other than the coralline I don't really have a lot of Ca/Alk
hungry animals...at least I don't think I do, I might be wrong.
<Disagreed -- Torch corals and Candy Cane's are both hard stonies, and use a good amount of Ca/Alk... would very likely account for any lacks here.>
Since I added the "bad batch" of salt on my last WC I have seen my Alk drop, my Ca drop and my Ph fluctuate more than normal as well as the coralline looking flaky in places and some on the walls with white
rings starting to form around them.
<This does seem odd -- I'd continue forward with testing a few buckets of mix, see if there's a trend towards imbalance with the Red Sea salt..>
I was always happy with the consistency of the IO salt, but didn't want to add say liquid calcium often over fear of the eventual chloride problem.
<Must say, I'm not aware of a chloride problem here -- as long as your dosing accurately and measuring, there shouldn't be an issue. Also, do look into solutions such as B-Ionic, they take a lot of the complication out of Ca/Alk dosing.>
Is there a way to use IO without a drip system, reactor whatever with a safer calcium additive, for a tank my size or is the 380 I get at 1.026 actually pretty good for my tank?
<Is about average, for non-supplemented water.>
I do use Seachem reef builder from time to time as well for Alk with the Red Sea Pro when it would mix the way it usually did: ph 8.3 Alk 7 and Ca 440. This bucket of Red Sea also leaves a noticeable amount of
deposit and "shiny" particles at the bottom of my bucket...so I fear I might have a quality issue with this batch.
<Hmm.. I'm beginning to fear this too, the more I read.. it does happen from time to time.>
Before I realized this was occurring I had done a 10% WC Friday which is when I noticed the parameters of my tank were starting to swing. From now on I will test EACH batch of mix, and at the very least every new bucket and a couple of batches.
<I would agree with this approach.>
I see a lot of different trends and guerilla techniques so to speak in these nanos but what I really want is a consistent stable and enjoyable tank, which I have been able to do pretty well before this last batch of salt got me worried.
<Smaller volumes of water are always problematic to keep at a stable chemistry -- which is why those in the know typically don't recommend them as a starter.>
Effort and maintenance is no problem, I just don't want to start out with numbers that aren't going to do my tank any good, especially in a small system such as mine. I appreciate your help, and I am so sorry if this is long winded, but my only other support is a fellow nano friend of mine who has sunk so much money and equipment into is tank he could have a 180 gallon reef with a sump! He's an engineer of course :-)
<Ah, always good people to know! Do look into/reach out to various BB's and forums around the net -- such as the one provided here at WWM! These forums are full of people willing to help and discuss their similar issues, successes, and failures.>
BTW, what would you do to iron this out? scrap the red sea batch and try to return the unused? mix the IO with the red sea (fear of a less than desirable effect with possible precipitation), or go back to IO and add something for the possible Ca issue if it is needed and if so what would you recommend?. If the consumption isn't too bad, will the coralline adjust to a balanced system with lower Ca?
<Personally, I would likely test 2-3 batches worth of the red sea at once (allowing them to circulate for 24-48 hours first). If I continued to get off/varied readings here, I would probably move forward with trying to get a credit on the unused portion. If you still have the Instant Ocean available, and its still testing accurately, I would use this for the time being in your tank.>
Again, sorry this probably simple and common problem is so long
<The proof is in the details, as they say -- this thorough description has allowed me to get a bit more of a view into the overall process that's going on, and I'm now more inclined to think it could be a problematic batch of salt. Let us know if you have any further questions! -JustinN>

Re: Premixed Saltwater Storage, Problematic Salt Mix - 10/06/2009
Hi Justin,
<Hey Keith!>
Well I do think I have a bad batch of Red Sea this time, like it is void of Mag or something. Today after adding my venturi to the powerhead in bucket 1 for over an hour testing resulted in a dKH of 18 ca of 280. Bucket 2 which was mixed later is a dKH of 16 Ca of 320 and finally the 3rd bucket with instant ocean dKH of 10 calcium of 380 still all at SG of 1.026.
<Mmm, does sound that way.>
Both batches of Red Sea are particulate
and hazy (even the mix from 48 hours ago!)
<Definitely not right>
My LFS has a good return policy and Reef Crystals from Instant Ocean is on sale by chance this week and will only run about $2 more than regular IO for the bag of mix that does 55 gals, so I'm thinking that might be my better bet as it seems I bought the last bucket in stock of Red Sea from them.
<Sounds like a plan to me. Reef Crystals is a quality product with a proven record.>
I know all salt mixes can have a bad batch, which is why it is important to test but the Instant Ocean has been pretty consistent....
<Agreed. Some have a better track record than others, but everyone has incidents -- it happens.>
its what I have used in my brackish tanks for years so I am hoping Reef Crystals will be just as consistent with a little better mag and Ca. Should I do small 5% water changes or should there be no harm in ionic balance to do a 10% weekly until my levels are more consistent?
<No harm that I would see -- the balance shouldn't be enough off either way to cause a precipitous event.>
Should I use a 2 part Alk/ca additive in the mean time like C-Balance or Kent A&B?
<Certainly, these are easy to apply and work well -- I like B-Ionic myself, but the above are fine too.>
Thank you for the help and the quick response.
<Glad to be of service! -JustinN>

R9: Green Hair Algae Problem (Ready to quit!)'¦Ozone & Water Prep -- 09/09/09
Hey Eric:
<<Hi Cindy>>
I read "Bob's" section on ozone last night (only my husband had read it before) and went ahead and ordered an ozone injection system from the show as well after reading it myself (put my apprehensions to rest).
<<Ah good'¦is a beneficial addition>>
Hopefully the rest of my initial order (skimmer, membrane and pads) will be here in a day or so.
I am already feeling so much better about my reef (my husband is having heart failure over the cost however even though I had warned him that they were a "money pit" right from the start) and that I may finally have this situation foxed thanks to you and "Bob".
<<So glad to have helped>>
Mr. Fenner is right, discus and planted aquariums are very expensive indeed but at least "around here", REEF RULES IN THE COST DEPT., probably because there are so few of us that do saltwater.
<<Maybe so'¦ (Can't help but to keep pushing the NET on you re)>>
I'll start cooking my water for at least a week as he suggested and seeding is a great idea and will make water changes much easier on the corals.
<<Indeed'¦ Many hobbyists don't realize how active/reactive newly mixed saltwater is, or how irritating/stressful it can be on your tank's inhabitants'¦and maybe even contributory to nuisance algae issues such as yours>>
That book (a real smart low cost investment in your reef systems) and you have been so incredibly helpful!
<<Redeeming to know>>
Do you have pics of your reef online? Must be something!
<<I did have some posted on my local reef club's website at one time, until we had a 'glitch' that wiped out the photo library'¦just haven't gotten around to taking/posting more>>
<<Happy to share'¦ EricR>>

Re: Cyanobacteria/BGA 4/4/09
Hey Scott,
I got this new vertical 70 gallon water storage tank from this Rotonics company. It's for my service van. Anyhow...i took a whiff of the inside and it kinda stinks like some chemical preservative or something like a Crayola crayon box or something.
<Hmmm, normal manufacturing smells.>
How do you recommend curing it?
<Just run some water through it....it will be ok.>
I submerged the lid in my pond and filled the tank with hose water. I figure once algae starts growing in it then it will be cured perhaps? Any ideas?
<No algae! Just rinse it a couple of times, then use away!>
<Welcome.><<RMF might scrub out and let soak with rock salt for a few days.>>

Marine replacement water for water changes 1/26/09 Hello, i hope this isn't too dumb of a question, but I was wondering how long water can be kept after it has been made up. <A good long while... particularly if it is covered... Months at least> Not having great tap water or a reverse osmosis setup, I get mine from my LFS that has a wonderful self fill station of salt water that is reverse osmosis and has a SG of 1.020. I keep my tank at 1.022 so I do have to add a bit of salt mix, but I keep the bucket(s) covered. Does the water need to have a pump in it for storage or does it need to be stirred only before adjusting the temp and replacing. <Can be used "right out of the bucket"... i.e., it shouldn't "settle out"> How long can the water be stored before it is considered old or stagnant? <Ages> On a side note, do you happen to know roughly how many tablespoons it would take per gallon to change the SG from 1.020 to 1.022? A half cup of salt seems to make a gallon of water have a SG of 1.021 from my tap, but I am guessing the reverse osmosis water might be a bit different. <Mmm, only if you have appreciable dissolved solids...> Any help would be greatly appreciated. Keith <Mmm, well... can you tell me how many tsps there are in a cup? Given your stated relationship twixt the salt mix and spg... this should be a relationship of the equivalent of how much a tbsp. out of a half cup will "move" a gallon of water one thousandth (0.001) in density... Yes? Bob Fenner>

Prepared Saltwater Storage -- 10/24/08 Dear Crew, <<Hello Linda>> My joy at finding your site in my 60's has/is a wonderful learning experience. <<Ah!>> My fish in the past would have appreciated the knowledge I am now acquiring through months of reading your marvelous site. <<Excellent>> My question is when I have prepared my salt water for the next water change, is it alright to cover the bucket with a lid? <<Sure'¦In fact some would say that 'dark' storage is best to retard biochemical/biological processes, though if only storing for a week or two I don't think this to be critical. But covering the container will certainly help with keeping out airborne dust/pollutants'¦just be sure to aerate the water for a couple hours before use to boost oxygen levels. Or if the lid is not an airtight fit, run a powerhead or airline with the lid on>> When I set the tap water out in the buckets and then aerate them, I cover loosely with a plastic sheet for gas exchange. I have read this is important. <<Indeed>> Thanking you in advance and thank you for bringing me many hours of learning and laughter. Linda Rich <<A collective effort'¦quite welcome. Regards, Eric Russell>>

TDS Readings'¦Leaching Storage Container -- 07/16/08 Greetings All, <<Hello>> THANKS in advance for a wonderful web site, <<Quite welcome>> unfortunately I couldn't find an answer to my question/situation so I must pick a few brain cells. <<Not too many I hope, I only have a few left'¦and many of those have been allocated to destruction via alcohol consumption [grin] >> I have a 7 stage RO/DI set up in the basement; the water drains in to 2 55-gallon blue barrels that are food grade--they had tomatoes in them previously <<Okay>> --the 2 barrels are connected via 1-inch PVC at the bottom so that as one fills, it fills the other. <<Understood>> As needed, I pump water into a 3rd 55-gallon barrel for saltwater changes one week prior to its use. <<Sounds good>> My TDS readings are at 001 out of the unit, and within the last 3-4 weeks the water in the barrels has started reading anywhere from 35 to 80ppm. ANY IDEAS????? <<I'll assume you are not adding buffers to these containers (would expect much higher TDS readings if so), so this is likely the result of something 'leaching' from the containers themselves. This may be something that was previously absorbed from the tomatoes, or something from the barrels makeup. You say these containers are 'food grade' but that doesn't mean they don't/won't leach chemicals'¦it just means that whatever they leach should be safe for human consumption. Water is a universal solvent'¦some leaching is not unexpected, even were these 'new' containers, and I think it likely they are indeed safe for your intended purpose here. You could take a sample for testing (perhaps at a College/University laboratory) if overly concerned, but if your tank inhabitants are not displaying any unexplained issues of late or nuisance alga hasn't sprung up unexpectedly, I would be inclined to ignore these readings and continue as you have been doing. Regards, EricR>>

Re: TDS Readings'¦Leaching Storage Container -- 07/17/08 Eric, <<Bill>> THANKS for the speedy reply. <<Quite welcome>> My fish and corals all appear to be doing fine. Polyp extension is very good, and colors are unchanged. <<Very good>> I have noticed however, a red slimy substance that has started to cover a portion of the algae and rock in my 'fuge, but not in my tank. <<Cyanobacteria'¦and not uncommon in these typically low-flow environments>> I do remove this red slime by simply using a 'fish net'. <<Good>> The only thing in my two 'storage' barrels is the RO/DI water, no buffers or any other additives. <<Okay>> There is an airline with a 'T' on the end in each barrel for circulation, and a heater is used in the winter. Due to the increased TDS readings in the stored make up water, I drained both barrels last Sunday, scrubbed the two containers with a VERY mild water/vinegar solution and thoroughly rinsed then dried with paper towels as I did prior to their initial use, and started the refill. <<All good, though this may only have a short-term effect'¦time will tell>> ALL filters/media in the system with the exception of the 100 GPD membrane, (it was replaced in March), were changed on Saturday, and allowed to run for 3 hours before collection. I am seeing a definite increase in green algae on my substrate and glass, but I attribute this to new 20 k HQI bulbs put in last weekend (They replaced 10 k bulbs). I have cut their 'on time' down to just a little over 8 hours from 10. <<Lighting is but a part of the nuisance alga equation'¦and I am not a fan of reducing the photoperiod to battle such as I feel this does more harm to your desirous photosynthetic organisms than to the alga. I can't say whether the appearance of the green algae (and/or the Cyanobacteria) is attributable to your water storage barrels'¦but I once had a 'previously used' Polyethylene barrel for storage of my RO/DI makeup water that I attributed to nuisance alga growth. I replaced the barrel with a 'new' one, and the nuisance alga disappeared within weeks. Coincidence? Maybe'¦but still something to consider>> So as long as my readings straight out of the RO/DI unit continue to read 001 I'm good to go--OK. <<Too nebulous'¦ Let your tank/common sense be your guide here>> At what point/level should I be concerned with the stored water readings, if at all?? Bill <<That's a tough one Bill'¦not knowing what element/substance is registering on the meter to begin with. If the algae you mention doesn't become problematic and the fish and coral stay healthy then no problem. If things start to go downhill then you need to try to determine the reason and the source'¦with contamination from the storage barrels being but one of the options. Regards, EricR>>

R2: TDS Readings-Leaching Storage Container - 07/19/08 Eric-- <<Hiya Bill>> Again, THANKS for your response. <<A pleasure>> I went by the facility that I have been purchasing my filters etc. from on my way home form work this morning--his price is way cheaper than any LFS in my area-- <<Give these guys a browse: http://www.thefilterguys.biz/ >> it is a home Water purification store, and as we were discussing the recent events of my water situation, we came to the conclusion that the GPD membrane/filter is bad. <<Mmm, maybe so'¦but your DI resin cartridge would be (is!) cleaning up any 'leakage' of ions through the membrane. A bad membrane should really only result in the faster exhaustion of the resin>> At his suggestion ran a 'test' of it the night before, and after 15 minutes I had collected less that 1 gallon of RO water, so I ordered a new membrane. <<I don't know that this really proves anything here, Bill. I get the logic that a 100gpd membrane should process at least 4-gallons per hour (e.g. -- 1-gallon every 15-minutes), but these 'ratings', while likely in the ball-park, are subjective to a bit of marketing hype/over evaluation just like anything else (e.g. -- the skimmer that's good for 'any' tank from 25 to 300 gallons). Water pressure, level of impurities, and very importantly water temperature (the colder the source/ground water the more waste-water produced per gallon of filtered water'¦and thus a slower filter 'rate') also affects the performance of these membranes. My own 100gpd unit runs fastest at this time of year here in the South, and my source water starts off with an already low TDS of about 80ppm on average'¦but I don't think that it is producing a gallon of purified water every 15-minutes'¦though I have not bothered to measure this. And a suggestion'¦if you don't have one already, the small amount of money to add a 'membrane flush-kit' to your filter setup would be well spent>> It will be in on Monday. He also stated that these membranes need to be stored in a refrigerator prior to their use, as they will deteriorate just sitting on a shelf, and it is quite possible that I received a bad one to start with, and suggested I have it replaced under warranty. <<Hmm'¦can't say I agree with all this>> Although this sounds good in theory, I'm a little leery of receiving another bad one, and going through this scenario again. I also discovered that he has 55 gallon barrels in stock, the price is higher than I paid for my current ones, but they are brand new food grade barrels, and have never been used. <<I ordered mine form USPlastics.com>> He also showed me some water storage barrels that he has leftover from the Y2K scare that are also brand new/food grade and are plumbed for water delivery. <<Ah yes, mine came with 'spouts' as well'¦very handy>> They come in 250 and 125 gallon size. The 125 is not much more in price than 2 55 gallon barrels and has a smaller footprint that 2 55's---SO in light of recent events, and not wanting to jeopardize my corals, I'm going to pick up one of these tomorrow--Friday-- and start anew. <<And will hopefully eliminate this variable/concern re your water quality and the 'used' barrels>> I've also got a new TDS meter on the way as well. We'll see. <<Indeed>> Hopeful Bill <<Do keep me posted mate. Good luck! Eric Russell>>

R3: TDS Readings-Leaching Storage Container - 07/23/08 Greetings Eric-- <<Howdy Bill>> OK, first insert "Stretch's' line from 'Animal house' here-- "... What are you some kinda moeron?..."(and yes I know moron is spelled wrong) <<Hee-hee! What did you do know?>> I realized that I was using my TDS meter wrong on my readings of water entering my first container. I was just holding it under the water as it entered/filled the barrel. <<Ah'¦>> Hey, I got the reading I wanted-- <<Indeed [grin]>> I washed/rinsed out both collection barrels, dried them with paper towels, and let them air out. Back-flushed the system, installed the new membrane, found out that there was no restrictor anywhere in my system, <<The missing restrictor is the reason your filtered affluent rate was so slow (low pressure against the membrane), and probably not the fault of a bad membrane>> good thing Dan (owner of water supply store) got one for me with the new membrane, flushed the membrane for an hour into a 5 gallon bucket (collected 1 gallon in 15 minutes) and started refilling the barrels. Using a glass jar to collect water going into the barrel my TDS is 002, and the water in the barrel reads 002, after 24 hours of collection. <<Yay!>> Therefore, I have concluded that 'IF' I had been using the meter correctly I would have seen that my collection water was the same TDS as water entering the barrels. <<Very possibly so'¦although not at optimum efficiency re the missing flow restrictor>> I'm still unsure as to why my membrane went 'bad' so soon, I replaced it in March--4 months ago--at the same time I replaced all the other filters. <<Mmm, give the old membrane a try with the new restrictor in place'¦may not be bad after all>> Anyway, it's the weekend to do one of the twice monthly water changes, but I'm thinking maybe I'll do one every weekend for a couple more weeks. <<Up to you mate>> THANKS again for being here for all of us, I know I appreciate it. <<Is my pleasure to share>> Bill Fletcher in Kansas City, MO <<Eric Russell'¦in hot and muggy Columbia, SC>>

Mixing saltwater 04/09/2008 Hi WWM crew <<Hello, Andrew today>> I was wondering when mixing saltwater where you have to leave it overnight, is it suitable to use a large storage container a few times to mix the sufficient volume of water or do you mix the saltwater in separate buckets and gradually add the water to the tank. <<When the water has been mixed in large water tub, i drain out my water amount and then pump new back to the to the tank when i am ready for a water change>> Thanks for all the help Kind Regards Dean <<Thanks, hope this helps. A Nixon>>

Phosphate Leaching In Plastic Storage Vessel? -- 10/22/07 Hi Guys, <<Peter>> I recently bought a 30 gal plastic container from Lowe's. I started using this to store saltwater mixes for water changes. I have noticed that when I do phosphate tests on the water in the storage bin that phosphate levels up to 5 ppm are detected. The water used is from an RO/DI that gives a TDS reading of 0.00 and when phosphates are checked directly out of the RO/DI the readings are 0.00ppm. Are the new storage containers leaching phosphates into the water? <<If these are tests on 'water only' in the container (no salt mix introduced- ever), yes, your tests seem to indicate so>> If so, how do I prevent that or are there different containers that I should be using? <<You don't state what you bought...but I know many hobbyists who use the Rubbermaid® containers with no ill effect. Another option is to purchase vessels made purposely for holding 'potable' water...I use a couple Polyethylene drums purchased from USPlastics.com >> Thanks, Peter <<Regards, EricR>>

Re: Phosphate Leaching In Plastic Storage Vessel? -- 10/22/07 Thanks so much for the quick reply. <<Quite welcome>> I found a clear polyethylene drum that I will test under the same conditions. <<Excellent>> I believe the container I was using was indeed a Rubbermaid. Thanks, Peter <<Cheers, EricR>>

Green Makeup Saltwater -- 09/22/07 Crew- <Craig.> I mixed 35 gallons of makeup water for my saltwater tank about two weeks ago. The purpose of this, of course, was to let the water age. Trouble is, I forgot about it sat outside for about 10 days longer than normal. The water has taken on a decidedly green coloration. I know I have inoculated it with organisms from my tank by putting my circulation pump in it because I can see them swimming around in there. Is this water safe to use for water changes (that was its original purpose)? <Probably yes. But personally I would hesitate to use it, too. Besides the somehow disturbing colour you cannot be absolutely sure the phytoplankton that turns the water green does not produce any toxic metabolites.> Have I cultured "green water"? <Basically yes, but usually you start by seeding with specific and known phytoplankton species. Without a microscope and some literature you cannot be sure what species you have now.> I am inclined to just discard it to be safe, but if I have cultured phytoplankton it would be great to try using it in my system to feed the polyps, etc that I know eat this stuff. <Same answer as above. Although most likely safe, it cannot be excluded this phytoplankton may produce toxic compounds. To get rid of it you can run a diatom filter and/or a filter with very dense foam material, and don't forget activated carbon to bind and remove possible metabolites, too.> If it matters, the water has had salt mixed in with it the entire time it was outside. Thanks, Craig. <You are welcome. Marco.>

I want to make sure I have this water thing straight... Mainly storing/using RO and synthetic SW   7/8/07 Hi there everyone! First, I apologize this is so long - many questions, all gathered over the last 2 weeks of intensive reading. I have been reading your web site (made a a donation also, <Thank you :)> because I feel like I have read a small book in the past few days) about deep sand beds, skimmers, RO water, water in general, and other assorted stuff. Whew, what a bunch of information!...thanks for providing this site with all your answers to people's questions. However, I still have a few questions I did not see answers for. After reading about water, I want to make sure I have this straight: I have a Kent Marine Pro Hi-S RO unit (installed Dec. 06, primarily because our water company has regular outages (3-4 last year) that put us on boil water advisories, and are not always the best about notification...this way I have water to drink, as well as making my fish happy). This means I no longer need to carry buckets from my LFS guy - nice. However, because of low water pressure, it takes a few days (or more dedicated gathering from me) to gather all the water needed for water changes (a 29 gallon freshwater and a 29 gallon reef. If I read everything correctly, I can put the RO water directly in my reef tank (3 fish, ~20 corals of various types, although mostly SPS, somewhere between 25-40 lbs. LR, deep sand bed) without adding anything - as long as I put it in a 1 gallon container and drip it over the course of 1-2 hours to replace evaporated water. Correct? <That's a lot of work. If you just need to replace a gallon, you can just pour it all in at once. Just make sure your top off water temperature is relatively close to tank temperature. If it's right out of the RO unit it could be really cold. Now, if you're mixing Kalk solution or something like that, then it's prudent to drip it in. > After reading about buffering, should I automatically buffer it even before adding it this way? And if I store it while I am gathering 5 gallons in a bucket (usually 2 days of gathering), it should go into a covered container with a powerhead or airstone to circulate the water and prevent it from becoming stagnant, right? Or how fast does it go stale? <Are you doing all this just for top off water? Buffering (if needed) and circulation are good things to do for water changes, but usually unnecessary for small top offs.> As a Christmas present, my brother presented me with ~10 5-gal. buckets that were once used to keep kosher dill pickles. Will the pickle smell hurt anything if I store water in these containers? <I doubt it. The smell is probably from the vinegar and a little vinegar shouldn't hurt anything. However, if you're really concerned, just test the water's pH before using it.> Or should I try to clean out the buckets (don't know how, it seems to have permeated the plastic - overwhelming smell if you close the bucket up and then open it a few days later!). <Coincidently, many aquarists use vinegar to clean out buckets and equipment because it's a safe cleaner that dissolves calcium deposits. You should rinse out the buckets well, but I can't imagine you'd need to worry about any residual vinegar that might have penetrated the buckets.> Also, re:. adding saltwater - if I only add 1-3 gallons (less than 10% on my tank), I can mix up the water and add it without a 1-3 day prep, however, if I have more, I need to create it, keep it heated, and aerated...again in a covered container. Right? <This is the most prudent practice, yes. That said, if you need to do a water change in a hurry or in an emergency, just make sure the water is well mixed and close to tank temp, salinity and pH.> Also, how long does it take for mixed saltwater to go bad if there is no aeration? <I'm not sure what you mean by "go bad." However long you let it sit, you can always re-aerate it. If you're ever worried, you can always test the water's pH. Sitting water freshly out of the RO unit can sometimes be acidic. Aerating it should remedy this.> I read quite a bit mentioning this, but never with any general timeframes - it makes me think the water will go stale (fresh) or bad (salt) if I leave it unaerated even 24-48 hours, hence the questions. <I think you may be over-thinking some of this. If your water has been sitting for over 24hrs, just re-aerate it with a powerhead. :) > Thanks again for all your inputs and your fast answers to everyone's questions, <No problem. Thanks for writing.> Kerstin DeRolf :-) P.S. I know my current tank is crowded - I am hoping to upgrade soon. However, everyone is generally happy, so it must not be too bad for them - I just know I would like to have more room for all, so I am hoping to upgrade to a 92-gallon this fall (if my husband doesn't have a conniption). Thx again, Kestin:-) <Overcrowding with fish is especially bad for reef tanks. It will be good if you can upgrade to a bigger tank. Just try to resist the temptation to get more fish for the bigger tank. ;) Best, Sara M.>

Mainly storing/using RO and synthetic SW... Double-posted...   7/8/07 Try 2, in case it didn't go through the first time...I want to make sure I have this water thing straight... <You'll learn not to double-post here...> Hi there everyone! First, I apologize this is so long - many questions, all gathered over the last 2 weeks of intensive reading. I have been reading your web site (made a donation also (FYI for those who don't realize it's possible), <Oh, yes. Our Amazon "begging bowl" is at the bottom of most pages> because I feel like I have read a small book in the past few days) about deep sand beds, skimmers, RO water, water in general, and other assorted stuff, and I know I have much reading left to do. Whew, what a bunch of information!... thanks for providing this site with all your answers to people's questions. However, I still have a few questions I did not see answers for. <Okay> After reading about water, I want to make sure I have this straight: I have a Kent Marine Pro Hi-S RO unit (installed Dec. 06, primarily because our water company has regular outages (3-4 last year) that put us on boil water advisories, and are not always the best about notification... this way I have water to drink, as well as making my fish happy). <Good> This means I no longer need to carry buckets from my LFS guy - nice. <Ah, yes> However, because of low water pressure, it takes a few days (or more dedicated gathering from me) to gather all the water needed for water changes (a 29 gallon freshwater and a 29 gallon reef). If I read everything correctly, I can put the RO water directly in my reef tank (3 fish, ~20 corals of various types, although mostly SPS, somewhere between 25-40 lbs. LR, deep sand bed but no sump or refugium) without adding anything - I do it with a 1 gallon container and drip it over the course of 1-2 hours to replace evaporated water. Correct? <Should be fine... If the changes were a few gallons all at once, I'd suggest aerating the water... And of course, making any chemical and physical changes to it ahead of use> After reading about buffering, should I automatically buffer it even before adding it this way? <If needed, yes> And if I store it while I am gathering 5 gallons in a bucket (usually 2 days of gathering), it should go into a covered container with a powerhead or airstone to circulate the water and prevent it from becoming stagnant, right? <A good idea> Or how fast does it go stale? <Mmm, never really> On a slightly different topic...As a Christmas present, my brother presented me with ~10 5-gal. buckets that were once used to keep kosher dill pickles. Will the pickle smell (which has seriously permeated the plastic) hurt anything if I store water in these containers? Or should I try to clean out the buckets (open to a suggestion how, am leery of using bleach). <Do give them a scrub with "rock salt" or such... and a few rinses till there is no smell... I prefer the Rubbermaid Brute trashcan series... maybe with a spiffy wheeled cart, cover...> Also, re:. adding saltwater - if I only add 1-3 gallons (less than 10% on my tank), I can mix up the water and add it without a 1-3 day prep, however, if I have more, I need to create it, keep it heated, and aerated...again in a covered container. Right? <This is best> Also, how long does it take for mixed saltwater to go bad if there is no aeration? <Again... indefinitely good...> I read quite a bit mentioning this, but never with any general timeframes - it makes me think the water will go stale (fresh) or bad (salt) if I leave it unaerated even 24-48 hours, hence the questions. Thanks again for all your inputs and your fast answers to everyone's questions, Kerstin DeRolf :-) <No worries re the water going "bad"... the same molecules have been on this planet for billions of years...> P.S. I know my current tank is crowded - I am hoping to upgrade soon. However, everyone is generally happy (randomly checked levels, and other than an elevated nitrate (am getting a new protein skimmer), all values are as dictated (ammonia 0, nitrite 0, alkalinity 9dHK, pH 8.0 (before bright lights on), spg 1.026, calcium 420) so it must not be too bad for them - I just know I would like to have more room for all, so I am hoping to upgrade to a 92-gallon this fall (if my husband doesn't have a conniption). Thx again, Kerstin:-) <Heeee! Welcome. Bob Fenner>

Saltwater Storage'¦Is A Week Too Long? -- 06/24/07 Hi, <<Hello>> I have just got a few books out the library to learn a few more things about marine tanks and so far the water changes I've been doing the water I use I just mixed up and put straight in (probably not a good idea). <<Not in my opinion>> But now I read that you should mix up the water and then leave it for a while to mature. <<Indeed>> So I've gone out and brought 2 more buckets and I'm using one for the freshwater for topping up evaporated water and one for the mixed saltwater. <<Okay>> I was hoping you could tell me if this was a good idea or not or if the water would go bad just being left? (The water is left in the bucket for about a week). <<A week is fine mate, and will give the salt time to blend/chemical processes time to complete. And I do suggest covering the bucket to keep out light/dust and adding a small powerhead or air stone for aeration>> I've got a 25-gallon tank and the water changes I have been doing is about ten litres (size of bucket) around every two weeks. Hope you can tell me if I'm doing a good thing or not. Thanks <<Should be fine. EricR>>

Storing salt   6/9/07 Hello wet web, I have heard of people storing their salt in buckets and come to find that it has dried out. Can this really happen? does the salt need to be stored in the bag that it comes in? Mike <Mmm, not dried out... actually the opposite. Salt mixes (and table, NaCl for that matter) are hygroscopic... attract water... clumping together... Should be stored with little air circulation to prevent the product/mix from "turning into a brick"... But can still be used in any case... just not as easily water-soluble... Better... again, to mix, store, circulate ahead of use... as posted... BobF> Water change bio-filter & Ca/alk question   5/14/07 Hey guys- <Wes>     First off, as always, thanks.  I do believe I have read all the relevant FAQs, but I could be wrong, there's a lot on your site!  :-)   <Oh yes... and much more to go> Couple of quick questions (hopefully).  For my SW tanks, I use tap water (gasp!) mixed in a Rubbermaid container.  I am in the habit of doing 10% changes once or twice or weekly (40 reef, 50 FOWLR).  I have been immediately replacing the water taken with tap water (gasp!) adding a few drops (aprox 2mL) of AmQuel +(will switch to regular am-quel next time around), and then slowly adding in salt.  The water is constantly being aerated and there's a powerhead mixing up the solution.  The water usually is heated and stays around 75-80 degrees.  I'm a relative newby, but this seems to be working well and allows me to do frequent small changes.  My question is if the container constantly has SW in it, has a biological filter developed? <Mmm, maybe a bit> My tap water does have trace amounts of ammonia from the faucet, but it is undetectable in the Rubbermaid after AmQuel and storage (even overnight).  Is this because of dilution, bio-filtration, or the am-quel? <Or out-gassing likely> Would it be a good idea to put any amount of substrate in there for bio-filtration to build up, or would the widely varying chemicals and salinity wreak any chances of life? <I would not change your protocol> Getting rid of extra chemical additions would be nice.     Next, I have been dosing Kalk overnight to maintain pH and keep my calcium and alkalinity up (in the reef only).  I have no troubles keeping calcium at 400-440, but the alkalinity has suffered. <As it will with sole Kalk use...>   When I started the tank, it was around 130ppm, now it's staying around 90.  I was wondering if there is something askew because I use tap water to make the Kalk, or if calcium might be elevating and precipitating out the alkalinity <Bingo> though I have seen no snowstorms and no precipitation is noticeable on my powerheads or the like.  I was wondering if it would be a good idea to drip a pH raising alk supplement (SeaChem reef buffer) nightly while monitoring until the levels fall more into balance and then switching back to Kalk. <Yes. Please read here: http://www.wetwebmedia.com/calcalkmar.htm and the linked files above> Wes ps--  I have to mention that every time I email you guys I have to resist asking a million more questions than the ones I planned.  Time for more reading!  hazah for WWM!  HAZAH! <Heeeee! "Hey, I didn't get a huzzah out of that guy in the corner... Watch your sphincter!" (Mel Brooks', Blazing Saddles). BobF> R3: Gold Algae Plague Driving Me Mad - and speculations re SW mix usability 03/27/07 Hi Eric, <<Greetings Arno>> My light intensity statement is no contradiction to previous statements...: previously the tanks were lit by the same artificial means, but also in addition by natural daylight, thus receiving a higher light intensity than any tank imaginable solely lit by artificial means. <<Ah yes, you did mention exposure to natural daylight.  But (and just musing now), if the tanks were not lit directly; as from above rather than from the sides (the tanks were stacked, yes?), and also considering your latitude, just how "intense" was that sunlight I wonder?  And not to offend...but I seem to recall from living there that full days of sunlight were more the exception than the rule>> Under those circumstances the algae came into being and grew even faster than it does now.  I am more thinking along the line that I suspect that the light spectrum of the T5's is different than that of the MH's, which is perhaps causing the problem, not the intensity. <<A possibility, agreed>> ***(this is an excerpt from the previous exchange)  An interesting perspective...  But I must say I fundamentally disagree (and a bit taken by surprise)...and am more than a little interested in how you have come to this determination*** It's not so much me who has come to this determination, but I heard this from people that are well into chemistry; certain trace and macro elements will fall out/precipitate if you aerate artificial seawater for a longer stretch of time.  You can also observe this, as the container in which you aerate the water ill soon show precipitation.  In addition it can, to some extend, also be measured. E.g. calcium, KH, magnesium and strontium levels tend to be lower after several days than the first day. <<I understand your point Arno, and will agree to some extent on the precipitation of some earth/bio-mineral elements, but these small losses are also easily refreshed/replaced "if" necessary.  As for other "trace" elements (many of which we as hobbyists don't or can't test for), many are added to artificial salt mixes in quantities exceeding natural saltwater levels as well as some added to our systems through everyday means (feedings mostly)...I've even read speculation that some of these trace elements may even build to "toxic levels" in our tanks.  I feel it is more important to let all the chemical processes complete and the water age before use rather than worry over some small amount of precipitation.  I age my water in a covered container for three weeks on average, using a powerhead for circulation rather than an airstone, and have never found the amount of precipitation to be detrimental...I find it difficult to believe that aging/aerating artificial seawater for several weeks will render it "fundamentally unfit for sps" as you state.  Bob has a pretty good chemistry background, perhaps he will render an opinion re>> <Mmm, interesting speculations... and well-worth investigating. Ron Shimek had some assertions re the lack of utility of synthetic salt mixes period... Others have touched on precipitation issues... Within practical "reason"... weeks of storage, use... I don't find any such issues being valid... IO/Instant Ocean for instance is still used planet-wide for all sorts of SOP bio-assays, culture... RMF> gr's Arno <<Regards, Eric Russell>> What is the shelf life of sand-filtered organic seawater? 1/23/07 I can't thank you enough for your free advice.  "Please sir, may I have more?" <No pudding for you.>  I am setting up a 90 gallon marine tank.  I don't want to mix my own water, or buy it by the gallon at the LFS. <Why not?> Scripps Institute of oceanography in San Diego is about a thirty minute drive away, and they have a faucet for free public use that dispenses natural seawater which has been filtered through sand.  I want to store about 100 gallons of this water (in dark blue, virgin, plastic, fully enclosed 55 gallon drums) at my house (outside), and use it for weekly water changes.  This way I will only need to haul water from Scripps every couple of months.  The drums have threaded caps, and so can either be completely closed, or allowed to be open to the outside air.  The drums are also opaque, so sunlight won't get in, although the outside temp might be in the 90's during the summer.  Will this scheme work?  What is the shelf life of sand-filtered organic seawater?  What else should I consider/do before using this stored water in my tank? <I don't think this will work, the filtered sea water will still be biologically alive and will not be able to be kept long term, just a few days at most without quite a bit of work.  Please see here for more http://www.wetwebmedia.com/seawater.htm > <Chris>

Mixing saltwater in high temperatures   8/23/06 Greetings and thank you for your great website. <Howdy and welcome> I am new to the saltwater aquarium hobby and I have a couple of  questions about mixing saltwater.  I would like to mix saltwater for my weekly water changes in my garage due to lack of space and a two year old son that is fascinated by all things fish related. <Heeee!> Here lies the problem:  I live in the desert and after brewing the saltwater for a few days in the garage, the temperature is close to a hundred degrees when I go to use it, even if I "harvest" it early in the morning.   My plan is to mix the water in my garage but at a high SG for several days and then bring the water into the house; add cold RO water (no salt) that has been stored in the refrigerator; mix it for another hour or two; and then adjust for PH, SG, and temperature to match that of the display tank.  I understand that temperature affects SG and would consider it when mixing my "recipe."   Does this sound like a plan that will lead to optimal water quality?   <Sounds like a very workable plan> In addition, I am having difficulty maintaining the PH in my display tank but absolutely no problem maintaining it in my quarantine tank. <Mmmmm>   My display tank (24 gallons) has about 20 lbs of live rock and a 1/2 inch layer of live sand while the display tank is bare bottom with just PVC pipes, a heater, and a power filter.  I use the same water in both tanks.  Is it likely that the PH problem has to do with inadequate aeration in the display tank? <Mmm, possibly a contributing factor... but not alone>   And would an airstone added to the filtration compartment of the display tank help stabilize PH in the tank?     <Might, worth trying...> Thank You, Ande <Do you have an alkalinity test kit? Please read here: http://www.wetwebmedia.com/marphalk.htm and the linked files above. Bob Fenner>

Storing Premixed Water - 10/18/06 I have a 215G aquarium that I have filled with R/O water and mixed with salt that I was going to start adding cured live rock to this week. I have since decided to purchase uncured live rock and do the curing myself in some separate Rubbermaid containers. I was told that I didn't need to use purified water for curing the live rock since the water will have so much organics in it from the process.  I have well water that should work since it contains no chlorine.   Since this process is likely to take a few weeks, I'm now concerned about the water that I have in my aquarium. Will my premixed water be ok to store for a few weeks if I keep this water circulating in a dark & cool room?  I'm hoping that I won't have to purify and mix another 215G of water.   Thank you for your advice. <Kevin, should be no problem doing so.  James (Salty Dog)> Kevin   

Saltwater Lifespan - Synthetic and NSW 12/1/06 Hi Crew, <Hey Mohamed, JustinN with you again> I was told the synthetic SW mix should only be kept for a week at most or else it loses its properties but reading on WetWebMedia it can be kept for months. <If kept in a closed container and circulated, this is the case.> Must the synthetic SW mix be kept in a certain way by using an air stone, etc or in a bucket will be fine? <An air stone or powerhead, and a heater would be best... I personally use a powerhead and a heater in a covered food-grade trash can.> Likewise on NSW, how long can it be kept and under what conditions? <About the same as artificial sea water. Hope this helps you! -JustinN> Thanks    Mohamed

Storing Seawater >Hi there! >>Greetings! >I am hoping to be able to store enough seawater to last a couple of months at a time, is this ok? >>Yes. >Do I need aeration, filtration, access to sunlight etc? >>Aeration, yes, generally a pretty good idea. Prevents excess precipitation, keeps the O2 levels up. If it's natural seawater, then you definitely want to filter AND sterilize. I'd filter through something like a Magnum 350 diatom filter (usually used to "polish" water, removes very fine particulates). You may even wish to sterilize with a bit of chlorine to be sure nothing unwanted enters, then allow to set out, or use Sodium thiosulfate to dechlorinate should any smell remain prior to use. Other than that, I'd use a heater to keep it warm enough for immediate use should that be necessary. >Any potential problems? >>Only if it's not covered well, sterilized/filtered prior to storage. >Our seawater is very clean and lovely here. >>Nice, and nice on the pocketbook, too. >Cheers thanks for such a wonderful resource! Emma >>Quite welcome, and I'm glad you have this resource. I find it's far better and easier to use than salt mixes, encourage folks to make use of such (as long as unpolluted from runoff, etc.) whenever I can. Marina 

Storing Saltwater <Evening> <Please as a side note, do not use html formatting on your emails.  It makes it very hard to read, and it is very time consuming to remove.  Thanks.> Hello again and thanks as always for the wealth of information you guys provide. <Will pass along to Bob.>  I've looked thru the archives and cannot seem to find an answer to my specific question.  I broke down my 95 gallon saltwater tank yesterday, preparing for a move next week.  I have all of the water (nothing but water) in 2 large trash cans, covered, on the back porch.  I live in Florida, so it gets pretty warm in the afternoons.  My question is this, being that the water is exposed to a 20-25 degree temperature change every day, is there anything that I can do to preserve the quality of the water, is this temp. fluctuation going to have a negative effect on the bacteria in the water?  Thanks a bunch for your help. Dean <Well Dean, Most of your bacteria will be in the rocks, substrate, and on the tank sides.  If you can, the best way to ease a move is to keep the bottom of the tank covered in an inch of water or so and use a bubbler and air pump to keep the bacteria going.  Put some fish flakes or some sort of ammonia in there to keep everything going at least once to ensure the best bacteria continuance to ease or eliminate cycling of the tank again.  Also if your substrate and LR are in separate buckets give them some sort of water movement, like a power head to facilitate O2 conversion. Please do keep the prus objects from the tank like sponges tank decorations and anything else in saltwater as well and you may be able to set everything right back up with very little hassles.  The water itself will be fine, I would check it the day you put it back in  the tank to make sure no large ammonia nitrite or carbon dioxide accumulations have occurred while it was in the bags.  Good luck> <Justin (Jager)>

Synthetic salt/ph  10/20/05 Hi crew, <Mornin' Mohamed> I have been testing a South African manufactured salt. It has a ph reading of 8.8.<Wow> Is this to high for corals/fish? <Yes.> Thanks <Welcome. - Josh>     Mohamed. <<Likely just aerating and storing for a few days (a good practice for all mixes), will show the pH settling down. RMF>>

R/O storage trace nitrites  12/30/2005 Great work on the website! <Thank you> I have a new dedicated trashcan and Kent Marine R/O D/I Maximma 50GPD.  I am already finding trace amounts of nitrite in my brand new clean Rubbermaid trashcan. <Unusual... I would give this can/container a good scrubbing with coarse salt and a brush (new) followed by rinsing, soaking with freshwater> I have tested the R/O drip which is perfectly clean, but when my trashcan is full I am finding slightly detectable levels of nitrite after about 15 hours.  Any cleaning advice on the Rubbermaid or is the SUPER CLEAN D/I water causing it to grow bacteria so quickly I cannot stop it? Thanks!!!! Bryan <Am at a loss here. I would contact the folks at Rubbermaid for their input... and scrub the container as mentioned. Cheers, Bob Fenner> Heating The Make-up Water...How? - 01/11/06 Good Morning, <<Good evening>> First I would like to say thanks for your devotion to teaching people like myself. <<You're welcome...but not so much teaching as sharing...hoping to make a difference...>> I recently purchased an RO/DI system. (Got tired of hauling jugs back and forth from the LFS <<I would too.>> and wasn't so trusting with their RO water. <<Hmm...>> I purchased a 6 stage system.  (I know this may be overkill but I got a good deal on the net.) <<Tis fine>> My space is limited so I opted for a Rubbermaid 23 gallon rectangular (restaurant style) trash can as a reservoir.  I dumped the first batch and am now ready to start mixing my own water.  I will use a Rubbermaid 18 gallon tub to mix my salt in. (I apologize for making this a bit long, just wanted to paint a clear picture for you.) <<No worries mate, the "detail" is a good thing.>> From what I have read, I should aerate my water for 6 hours or so <<I prefer aeration for 24 hrs. prior to use to expel all carbon dioxide/allow pH to stabilize.>> and get it to 80 degrees before adding salt. <<Match the temperature in your tank.>> Is this correct? <<See above>> Here comes my dilemma.  Do you have an idea of how I could heat my water? <<Um, sure...use an aquarium heater.>> I considered adding a 200 watt heater to the mixing container, but am afraid the heater will burn a hole in the plastic. <<Small concern (if any at all).  I've been doing just this for decades...haven't burned a hole through any of my water containers yet <grin>.  As long as the heater stays submerged/there is water in the container it shouldn't get hot enough to melt through.>> Should I make a baffle type piece to mount the heater on? <<Can...is up to you.>> I am open for suggestions here. <<Of little/no concern really.  Just drop the heater in to the container or fashion a method to keep it off the bottom...your choice...whichever makes you feel better.  Do be sure to keep the heater submerged at all times.>> I have so many ideas running through my head now with other projects. (auto top off systems, sumps, etc...)  I guess I would just like to hear how someone else has accomplished this.  Thanks for taking the time to help another obsessed aquarium keeper. Steve <<No problem Steve.  regards, EricR>> -Storing premixed saltwater- I have a 55 gallon saltwater tank with 60 lbs of live rock, a few fish, SPS corals, anemones and many inverts. I make my own saltwater using distilled water <Be wary of distilled water unless you are absolutely sure it hasn't come in contact with any metals (especially copper) during the distilling process.> and keep it in a 18 gallon tank in my garage with crushed coral and a aqua clear 500 filter. I use the foam filter inside the filter and add a little carbon every other month to keep the water crystal clear. My question is: Should I keep the crushed coral in the 18 gallon tank or should I remove it and use only a bare aquarium to keep my premixed saltwater? <You don't really need anything in the barrel besides the filter and maybe an airstone> Should I take the crushed coral out and add a few lbs of live rock? <I wouldn't, because you will have to feed it, the critters will produce waste, etc.> What is the best way to store  the premixed saltwater so I can use it for quick and easy water changes? <Keep it well circulated and aerated if possible. Good luck! -Kevin> Thank you! Donovan

SALTWATER STORAGE >Hi, >>Greetings. >I have just started to store pre-mixed salt water.  I have a Rubbermaid trash can ( 20 gallon, didn't have room for a larger one).  I add the water and let my pump aerate it for 24 hours.  Then I add my salt.  How long should I aerate it then?   >>Keep the water in movement (either through powerhead or air stone) as long as it's being stored. >I have heard that aerating too long after adding salt can cause some important elements to escape; but I have also heard that water must be continually aerated to keep it from stagnating.   >>The only elements you'll lose are the salt itself from salt creep (if using an air stone). >My container is in the house so it stays cool.  Should I cover the can to keep it totally dark?   >>Best practice, my friend.  Keeps bad things out, eliminates evaporation.  Do be sure to bring the water to proper temperature before using. >How long will the water stay good in the container?  The water will last me for 3 weekly water changes.   Will the water stay good that long? (3 weeks)? >>Easily.  If we were looking for months, then I'd be more inclined to treat it as I would fresh potable water, and in that situation I would lightly chlorinate and have Sodium thiosulfate on hand for dechlorination if used before dissipation.  In other words, keep it covered and circulated, and you'll be golden. >Thank you for your help, James >>Most welcome.  Marina

WATER CHANGES AND STORAGE Hi, Hope things are going well there.  I have a couple of questions for you please.  First, After purchasing a plastic container to store sea water in for water changes, how should it be cleaned before use?  With salt? <Yes to cleaning... with rock salt, water and a clean "scrubby", then a good freshwater rinsing> Also I know the container should be covered most of the time to prevent contaminants, but I have heard as mixed sea water "cures" it releases certain compounds into the air.  Shouldn't the lid be left off sometimes to let these escape? <A loose fitting top (which almost all are) is best, adding a recirculating pump or powerhead is a bonus for stirring as well as warming, aiding you in pumping the water out> And lastly, I use a piece of plastic tubing to draw out old water before making a water change.  Would having the end of it directly on the substrate help get out more organics. Don't they usually accumulate closer to the bottom of the water column? <Yes... do look into "store-bought" gravel vacuums here. Many are well made for this purpose> As always, thanks for your good help.  James James Hall <Welcome. Bob Fenner>

Re: WATER CHANGES AND STORAGE Would the sea salt work to clean? <Of a certainty, yes. Just more expensive than plain "rock salt" for the job. Bob Fenner>

- Storing Synthetic Seawater - Same question posed thrice, answered by Kevin here Hi, I am currently pre-mixing my salt water in a Rubbermaid container for future water changes.  After aerating for 24 hours I add the salt. How long do I aerate after salt is added? <Until you use it>  I have heard not long due to loss of carbonates and I have also heard to continually aerate as long as the water is in storage.  <I'd either run a small powerhead inside or keep on aerating. It should be fine to use for weeks.>  My water storage lasts me for 3 weeks of water changes.  <Sounds good, Good luck! -Kevin>  Thank you, James

Saltwater too Salty - 8/28/03 Dear WWM Crewperson: I just made 32 gallons of saltwater for my storage batch, and I made it a bit strong, around 1.030.  I would rather not dump some out and add fresh water.  Can I add some of my top-off water to my water change bucket at the time of a 2-4 gallon change in order to bring it down to 1.025?  Thanks, Rich <Yes you can. Should be no problem. Bob Fenner>

Can I Still Use This Saltwater?  >Hi Crew,  >>Hello questioner.  >I'm back again with another 'newbie' question. (didn't have much look with the chat room, and haven't found anything in my shiny new copy of CMA).  >>Didn't have much look, or luck? In any event...  >Sixteen days ago I mixed 20 gallons of RO with Instant Ocean mix to 1.023 sg in a very clean plastic trash can. I didn't need it then as I thought I would, and it's been in the covered can in my garage (75-90F) since then. I planned to use it for a water change today and found a thin white "dusty" film of solids on the surface when I uncovered it. Substance doesn't seem to want to re-dissolve easily with stirring. pH still tests good at 8.0 and s.g. is only slightly over 1.023 (can be corrected I'm sure).  >>Yes it can.  >Is the water safe?  >>I don't see why not, if it doesn't smell bad. However, AERATE it for at least 24 hours before using, it could have a very low degree of dissolved oxygen at this point.  >More tests?  >>O2 saturation, or aerate.  >What's the white stuff?  >>Not knowing where you are, and being in southern California, my mind is on ash fall. I would take some paper towels and skim them across the surface to remove this stuff. If it goes with them, great, if not, then I might hook up a small power filter.  >I need to do a water change, but I'm scared of it. Should I be?  >>BOO! (Sorry, and here I'm just sick of Halloween..)  >Thanks for the great work you guys/gals do. Randy C.  >>Just be prudent and cautious, remember that the high temperatures will lower the O2, if everything else checks out ok, then don't worry too much. But do remove the film, I'd feel better if you did, and I like to visualize a grown man standing over a can of water passing paper towels over it, makes me smile. Marina

- Storing Saltwater - I mixed about 25 gal of saltwater (Reef Crystals) in a large Rubbermaid trash can for storage.  The water was filtered thought the Aquarium Pharm. tap water filter.  I also used a fairly powerful powerhead to dissolve the salt, but no heater.  It is in my garage which can get down into the 50's at night.  After a few days I achieved the correct specific gravity.  However, about 10 days later, it looks like part of the salt precipitated out of the water and is clinging to the sides and the bottom of the trash can as well as the powerhead. <More likely that this is the calcium.> It comes off easily if I rub it.  Is this due to the temperature drop? <I don't think so - solution was likely saturated.> The specific gravity has dropped from 1.026 to 1.023. <Fascinating - I wouldn't have predicted that unless your original reading was wrong... air bubble on the swing arm or something. Typically even salt water in storage will get saltier as water evaporates and salt does not.> Thanks, Randy <Cheers, J -- >

- Water Storage - Hello crew! Got one for you I will try to be brief. I have 2-45 gallon Brute trash cans for my water. I plan on having my RO/DI connected to these. Can I tie both cans together at bottom via bulkhead and a ball valve between them? <I don't see why not.> And if I install a float switch in the first can will both cans keep at the same water height without the second one overflowing? <I'm not sure that it will work... but it may. Would be something to experiment with.> Many thanks.. again <Cheers, J -- > - Mix Water Storage - Hi, Now that I am tired of mixing water every week I decided to set up a 35gal garbage bin with pre-mixed salt water. I filled it up, dechlorinated it, mixed in salt then put in a heater and a 300gph powerhead with a working air venturi. (Note: Our tap water is great here, all the aquarium stores use it with no problems.) My questions are, is there a shelf life for that water? <Well... as long as the water is well circulated and aerated, it will last a pretty long time - not years, but several months.> I only have a 33 & 10 gal tank and change a total of 7 gallons per week of water. So, this will last me about a month. <Perfect.> I leave the heater and powerhead on all the time. Also, do I need to leave the heater and powerhead on all the time or just run a couple of days before the water changes? <I'd leave the powerhead on 24/7 and heat only before it's time to use the water.> Thanks in advance. Darrin <Cheers, J -- >

- Storing Water and More - Crew, good morning.  Great site as usual... I had a few questions about a storage system for fresh and saltwater.  I plan on having two 44 gallon Rubbermaid Brute trash cans for water storage. <Ok.> One for fresh, one for salt. <Sounds good.> I will have a poly filter supplying the trash cans. <Ok.> Do I keep the lids on them all the time? <I would... keeps the bugs and dust out... perhaps a small hole so you can get electrical cords in and out.> Do I keep an airstone in each working at all times? <I'd use a pump to make sure the entire barrel is being turned over. An airstone would be extra but would do no harm.> Do I keep a pump moving the water at all times or only when I plan on adding salt? <I try to keep barrels full of water moving all the time.> Somebody in your crew wrote that it would be good to use a Mag Drive 500 pump.  Is this pump too much movement and do you keep it on at all times? <Actually... I think I have a Mag 7 in my water garbage can right now.> If it is too much, what would you recommend? <MaxiJet 1200 would do.>   Should I have one pump for each trash can? <Yes... would be cheaper to go with the Maxijets.> I plan on having these storage cans in the garage and I want to install PVC up about 10 feet, over about 6 feet and back down 10 feet into my sump in the living room.  I was thinking about an Ampmaster or Iwaki pump (unsure what size).  I will have a hardwired switch in the living room to manually turn on and off the pump to bring in top off water/salt water.  Do you see any problems/suggestions with this idea? <I think that would work... perhaps with some kind of secondary shutoff near the tank in case the switch stops working. You just can't be too careful with this stuff.> I don't really understand all the pumping problems.   Sorry for all the lame questions, but I am just starting and I want to get it right before I buy. <Not lame questions at all.>   Thanks for all your hard work and time spent.   Dan <Cheers, J -- >

Cigarette in my mixing water! Sorry for bothering you again, Blundell (or whoever is on duty for the day). << Blundell again. >> I have been preparing my saltwater in a 32 gallon Rubbermaid tub with a small powerhead for circulation.  As I was fiddling with my old tank, the cigarette (new and never lit) resting behind my ear fell into my Rubbermaid tub with the saltwater! << Doh >> I saw it fall in and quickly grabbed it out (so it was probably in contact w/ the water for maybe a second or two).  Have I contaminated my water and must I now throw away all that salt and preparation time put into it?  Thank you again! << No, I wouldn't worry about.  Personally, something that small wouldn't bother me.  I'd be more worried about the chemicals that were used to make that Rubbermaid than the cig that fell in. >> -Dennis << No worries, Blundell >> <... dismal... RMF would NOT use this water... Nicotine and many other tobacco ingredients/matters are too likely to be too-a-degree toxic here>

Storing & Mixing Water (8/8/04) Hello again! <Greetings. Steve Allen here.> Three quick questions... I need to get a container to pre-mix for water changes. In one post, Bob says, "Get/use a chemically inert, clean 'trash can'..."  In an article, I think he specifies "Rubbermaid" brand.  Of course, I will buy new and dedicate to the task, but how do I know if they are safe (chemically inert)? <Anything recommended for food should be fine. I'd expect most brands of plastic ones to be fine.> Is any Rubber-maid OK?  Other brands?  I would like to get a wheeled tote about 35 gallon or so.  The Rubber-maid with wheels has metal reinforcements for the handles on the inside of the can. I looked at another brand that didn't (Dura-bin? I think) that was brown plastic and square. Recommendations? <The Rubbermaid Brute has served me well. The one I have has no metal parts. I put mine on wheels for ease of use.>   Will my old Mag 5 pump work in place of a powerhead to mix the solution? <Just set it up so it does not spurt water up and out of the container. I use a hose to pump straight from the can into my tank in the next room.>   I don't know how hot heaters get on the surface. Can they melt the plastic garbage cans if they come in contact with it, or should they be rigged away from the sides? <Unlikely to get that hot when in water. However, I use the plastic sheath that one can buy for specific brands of heater. I use a Hagen Tronic and the sheath they sell for it.> If the latter, how do you do it?  Ooops, that was more than 3 questions, wasn't it? <No problem.> Thanks! Greg Smith <Hope this helps.>

Water storage Happy New Year to Bob & crew! <Good morning> I recently got 2 blue plastic 55 gal. barrels for use as water storage containers.  Allegedly used for wine transport by a local winery. Intent is/was 1 for SW mix, 1 for R.O. water.  I have washed them out twice with hot water & chlorine bleach, de-chlorinated with Aquatronics "De-Chlor", & rinsed twice.  I still end up with a thin film (scum) on the surface  when I fill with R.O. water.  The distributor said they were just "steamed" out, but since they are a large barrel recycler, I don't know if they used any kind of cleaning agent, soap or ???  In your opinion, am I taking an un-necessary chance with these barrels?  Would running a canister filter with carbon help to remove any potential contamination? <I am suspicious too... and would not use these tubs just yet. Are they polyethylene? If so, they may have to be "cured" over some time to remove whatever the residue is. For now, try scrubbing them out with rock salt, a little water and a tough sponge... and let very salty water sit in them a week or more... drain, rinse, see if the scum is gone. If not, we'll talk over what you might do next. Bob Fenner> Thanks, Neil

Mixing/Storing Saltwater I have a question about keeping saltwater for water changes and for make-up. I want to pre mix salt water in a plastic 30 gallon container, if I keep an airstone in the water how long can the water stay fresh or does it go bad? <Well, I don't think that it will necessarily "go bad" after a certain time, but evaporation may occur, resulting in a higher specific gravity. Perhaps there may be some dissipation of compounds found in the water over time, but probably not in amounts substantial enough to impact its usefulness, IMO. I generally mix up water just before I use it (i.e; a couple of days).> I have tried this and noticed  a odor  from the container. Does this mean that the pre made water has gone bad? <Maybe it has not "gone bad", but there might be something in the container dissolving into the water, or perhaps the container did not completely dry out after its initial use, and you are smelling mildew or something...? If you smell a sulfurous smell, then there may have been some anaerobic activity occurring in the container when it was "empty", and you're just smelling the end result. Hard to be sure from here.> If you have any suggestions I would appreciate any tips. Thank you. HAPPY HOLIDAYS !! Sergio. <Well, Sergio, as outlined above, I'd make up the water as I need it, and clean out and dry the container after each use. I'm sure that you'll be fine. Good luck to you, and Happy Holidays to you, too! Regards, Scott F> Water Storage Question I am trying to line up everything for my new tank. I am setting up a 180 gal. reef ready but FOWLR for starters. <Nice size> My question is in regards to storing water for my water changes. A friend of mine was able to get me a 55 gallon plastic drum that was used to store honey. (His friend works at a big cracker factory). <Yummy> Would it be ok for me to was h this out with hot water and use it for water changes? <Should be, yes> I will have to cut a hole i n the top about 6-8 ' in circumference in order to put in the salt, heater, and a pump. If this is ok how long can store the water? <Indefinitely> I plan on getting two of these drums and always have one ready for action. <Good idea> Thanks in advance for the info! <Please see here for more: http://www.wetwebmedia.com/water4maruse.htm and the FAQs (linked, in blue, at top) beyond. Bob Fenner> Dave

How to tell if a plastic is toxic? I went today to Home Depot trying to get a plastic bin for a) making and aging salt water b) using it as treatment tank for sick fish and also for quarantining new fish. I've heard there are some plastic that can be very toxic to fish, even if just used to mix the water and salt (brief period) but none of the buckets and bins were labels as water/food safe or gave any other indication. How can one tell which plastic is good and which is the bad one? thank you, Luke <contact the manufacturer or be conservative and simply avoid any that do not say food-safe, my friend. There are so many plastics available and most nearly every one is safe. Anthony>

Planning Large Reef w/Water Reserve Hello Bob, I am now in the concept stages of planning my dream reef tank to coincide with the purchase of a new home 18-24 months from now.  <Ahh, good to plan, anticipate> It will be an in-wall ~1100 g 12'x4'x3' tank with LR/LS optimized for SPS corals, 2 mixed shoals of Anthias and some other hard to keep, but compatible, favorites on my list. <Wow, some system!> I read through the large-tank/designer-tank/circulation/plumbing/mud FAQs and still have some questions. I ask these questions, because I would rather spend the money once going REAL SLOW and be happy with the results. <We are in agreement with this approach, philosophy> I received a burst of inspiration to add a very large water reserve to my tank plans. It came from an UK-based hobbyist magazine article on a 2300 g water reserve attached to a 1200 g tank with 300 fish and "wall to wall" corals. This at-home system had lots of attached commercial equipment, but it gave me ideas for 2000-2400 g of extra water. First of all, are you familiar with any similar setup in the USA or the article I am referring to?  <Think I saw the article in a recent PFK issue, and yes... many folks have sizable reservoir, water storage facilities> What is your opinion on the large water reserve concept?  <A good one. My memorialized opinions re can be found here: http://www.wetwebmedia.com/water4maruse.htm> With respect to gas exchange, should the large water reserve be a open top container or would an buried water tank serve the same purpose if the main aquarium had adequate circulation installed? I would also like your definition "adequate" as I could not find a similarly configured system in the FAQs. <Should be recirculated, heated... best to use an external pump, pump from bottom, discharge at surface in such a size, type arrangement.> I am leaning heavily towards EcoSystem Filtration (with light skimming as you recommend) with two 200 g mud sumps for redundancy, increased bioload potential, and room to hold water in case of power failure. After the tank is well established with critters, I plan to add a mated pair of Mandarin fishes. With Leng's system, would an additional refugium be beneficial to the Mandarins?  <Yes> If so, would you recommend a sand bed to complement the mud for added critter diversity, or would a 3rd mud-sump/refugium be the better approach?  <Sand> In preparing for the Anthias and Mandarins, would it be wise to start the refugium a year prior to the large tank? <Not so much time, but a good month or two> Finally, I was considering using an actuated ball valve to control water flow on two alternating pathways on a closed circulation loop from a pressure rated pump. The loop would feed a PVC structure hidden behind the rock work. This would be in addition to 4 Sea-Swirls used as returns from the sumps from a non-pressure rated pump. I have two thoughts here. First and foremost is redundancy in the circulation plans in case one pump fails. The second is having the top 8"-12" of the tank as an open water column with chaotic water flow for the Anthias, some carefully selected Surgeonfish, and some Green Chromis dithering about to keep everyone at peace. What are your thoughts on actuated ball valves used for alternating circulation loops? <Generally unnecessary... better/fine to have all the water pressure, flow discharge in a chaotic fashion w/o the expense, restriction of valving. Try the set-up w/o the valves first and see if you still consider them useful is my suggestion.> Would you consider the Sea-Swirls overkill? Am I missing something here (including simplicity)? <Other circulation is worthwhile> As a side note, I am returning to the hobby after 12 years. After reading about 8 or 9 books on the hobby last year, I must confess that I enjoyed the CMA the most. I truly appreciate your ongoing efforts on WWM and the efforts of your colleagues in establishing a treasure chest of information! <Ahh, thank you for your kind, encouraging words. Will share. Bob Fenner> Thanks for your help.- Rob

How Long Can You Keep New Saltwater Around? Good morning, Me again and so far so good with my tank.....feeding as advised and I think that all is well for the time being. My question....I had quite a bit of salt water left when I was curing my rock....about 25 gallons or so.....when I thought that a major water change did not seem likely I put the plastic garbage can with a tight cover in my basement (around 40 degrees) I have it set up so that I can run some air in it and put the heater in it before water changes.....but....right now it is off.....I knew I wouldn't be doing a change for a while as the tank was still showing a bit of nitrite and I wanted to leave well enough alone.....I think it is now time to start my weekly changes. How long will that water be OK? <As long as you keep it covered, it should be ok for awhile. The only consideration is for evaporation elevating the salinity.> If I just plug in my pump and heater for a few days should it be OK or does it ever rot.......I can mix up some new stuff but I hate to throw that old water away...It's been in the basement for almost 3 weeks..... Thank you and have a great day...Helene <Double check the salinity, heat to appropriate temperature, and aerate well to reach peak dissolved oxygen and you should be just fine. -Steven Pro>

Salt water storage Hi everyone- I was hoping you folks could help me. I keep a 40 gallon dark blue Rubbermaid tub with my premixed saltwater and have a heater and a 120 gph powerhead in there. I always keep the lid on it. <All sound practices.> This batch has been sitting about a week or so. I took the top off and I have some sort of black looking algae starting to grow on the sides in the current. I tested the water for phosphates and nitrates. Phosphates were nil but the nitrates were around 25ppm or a bit more. It also smells a bit "beachy". <Ok> I run the tap water through a filter that filters out pesticides, chlorine, sediment, some metals and VOC's and some other stuff. <Is this an Aquarium Pharmaceuticals Tapwater Purifier? Your description of what it filters sounds just like the wording off of the side of the box. If it is one, you should not have any nitrates. The TWP should have taken care of it all, unless the cartridge was exhausted. Double check for the color change.> I have tested the tap water before and have had no nitrates or phosphates. My question is, is there something in my storage process that could create the nitrates? <No> I would hate to throw out 40 gallons of mixed water. Is there any way I can remove the nitrates? <Yes and no. Nothing practical. If the cartridge was bad and it allowed nitrates to go through, there are other contaminants present that you cannot test for. You will have to discard the water if I am correct with my guess.> I just started doing the water storage routine a month or so ago. I had been mixing the water and adding a dechlorinator/chloramine and letting it sit for just a day. Since I have started this water storage routine I have had a major explosion of red algae. Is there any way these two things could be related? <Possibly related, although it could have been something that was warming up and happened anyway after switching to the storage routine.> The filter for the tap water is also new. <I would double check the cartridge anyway. I had one of these years ago and I never was able to make more than 40 gallons of clean water before I had to replace the cartridge.> Any help would be appreciated. Thanks, den <Talk to you later. -Steven Pro>

Re: Saltwater Storage Steve- Thanks for the quick reply about the stored water problems. It is not a Aquarium Pharmaceuticals filter. It is a double canister under sink filter, the description of each canister is below. The filters should still have months of life left. I have only ran a few hundred gallons thru. Filter 1....This cartridge is utilized as a Stage 1- Pre-Filter in our Twin Ultimate Water Filters. Combining the highly adsorptive efficiency of an extruded Carbon block with several layers of sediment prefiltration (5 microns) to effectively reduce Volatile Organic Compounds, Chloroform, Chlorine, THM's and other pollutants. It also increases the overall life and effectiveness of the Stage 2 - Doulton Ultracarb Filter Element. Typically lasts for a full year, about 2,500 gallons. <Sounds fine.>  Filter 2....Combining KDF, a compound of Copper and Zinc, <Oh... I don't like the sound of that.> and Granulated Activated Carbon this filter acts as the Stage-1 filter in our Undercounter Twin Superior Water Filter. Works especially well on Chlorine, Iron, Sulfur, Lead, heavy metals and many organic contaminants (VOC's) including pesticides, herbicides and trihalomethanes by using reduction-oxidation techniques combined with the adsorptive nature of activated carbon. Lasts for about 2500 gallons. Could the copper and zinc compound in filter two cause a problem in the tank? <Yes, could give you problems. Anthony and I were just discussing the usage of zinc orthophosphate in our local tapwater and how one of our big local freshwater fish breeders has experienced a rash of congenital defects from its introduction. His gentleman is going to RO water for many of his tanks and still has some problems. Both Anthony and I suggested he use RO/DI and have his product water tested for contaminants. I would be very leery of this product. You will probably notice problems with your inverts first.> If a filter filters out chlorine would it filter out chloramine also? <I am not sure.> I ask because chloramine is not mentioned in the list. <Yes, conspicuously absent?> I have had unexplained (to me) deaths of 2 cleaner shrimp, 1 sea anemone, and several hermit crabs in the past month. It seems like the blue leg crabs are dying but the red are fine. Don't know why. Any thoughts on that? <It could be the water. It could also be many other things. There is not enough information at this point.> The fish (Naso Tang, Sailfin Tang, Yellow Tang, Regal Blue Tang, and Damsel) have all been doing great. I always match change water as best I can. I am in the process of upgrading into a 125 gallon tank and I was hoping I could clear up this problem before the move into the new tank a month from now. <I would strongly suggest a RO unit. Take a look at the SpectraPure line. That is what I sell.> If I am mixing and storing the water for a week do I need to filter it at all? <I prefer to use purified water whenever possible and I recommend it most times.> We are on Atlanta city water. Not the greatest but good. <I have been there a few times. My sister-in-law and her family live in Kennesaw. There was a very nice store in Buckhead, can't remember the name. My sister-in-law's water seemed ok there, but the one local tank I saw used RO water. He had extreme hair algae problems when he was using city water.> Thanks again, Den <You are welcome. -Steven Pro>

Saltwater Storage I'm in the process of setting up a 125 gallon FOWLR system. I have been doing a lot of reading about mixing salt water, but still have a question. I'm using a 44 gallon garbage can with RO water, a power head, and a heater to premix my water. I let the water in the garbage can heat up to tank temperature, then add salt mix and stir with powerhead. My question is, after I mix the salt water to the right salinity can I store the container without the powerhead and heater? <Without the heater would be ok, but leave the powerhead to keep the water from stagnating.> and if so for how long? <A week or so> Thanks in advance, Mike <Please remember that you will have to reheat to the appropriate temperature before use. -Steven Pro>

Pre-mixing and storing water Hi Bob, In your WaterChgFAQs (http://www.wetwebmedia.com/waterchg.htm), you mentioned that you have a detailed approach to pre-mixing and storing water at the www.wetwebmedia.com site. I have been looking around on this site, but I could not find it. Could you point me in the right direction? Thank you, Jim PS: The search feature of www.wetwebmedia.com was not working either. It returned a "Error from search: can't open the word hash file D:\wetwebmedia\web\_vti_txt\default.wti\All.dct" error. <Jim, thanks for these notes... believe me, do appreciate them. Though I'd much rather be sorting, identifying, scanning and placing my latest photographic efforts from Australia (some fun now!) on the WWM site, sending cover submissions off to mag. editors, the photo bank... Even eating Lima beans... do know that there is much, too much amiss on the site currently (and feverish need to add a few hundred already written pieces on the industry, surveys of groups, adventure/dive travel), let alone strategic trials at adding video, slide shows, chat rooms... Be all this whining as it is, did try to look/find the "detailed" pre-mix instructions part (have in the CMA book, but where oh where on these dastardly HD's?). Have keyed a run at this and placed here: http://www.wetwebmedia.com/water4maruse.htm along with spiffing up spellings, appearance on related pieces... once again at your prompting. Thanks again, you necessarily cruel taskmastah ;) Bob Fenner>

Re: Water Changes Bob, Thanks for the replies. I have visited your site and printed off the details on alkalinity etc. Couple of questions though: When you say "store the water, aerate for a week" do you mean actually aerate it for a week??  <Well, actually no... but to keep the water in motion... if folks are only using a mechanical aerator to mix their synthetic, yes... better to keep this pump/stone running... Much better outgassing of sanitizer, complexing of ionic metal, mixing of artificial salt components... and less likelihood of capillary action/siphoning of water out of the container... Yes, mundane to ridiculous considerations... but real. Better than a mechanical aerator is/would be a small submersible pump, powerhead... that can be easily rigged to help pump/move the new water into the main/display system(s), and possibly contribute its/their waste heat to warming the water...> Most places I read say aerate it for a minimum of 6 hours. Whilst I accept there is no "maximum" it seems an awful long time -what are the benefits? <Would you like more?> I already use the Instant Ocean salt mix - it seems I may have been over supplementing - another local fish supplier recommendation due to the use of de-ionized water! <I know of such suggestions... and disagree with them... if you drink, cook with the water used, it is likely fine for aquarium use... If you have doubts, concerns, have your source water tested (by a lab, the water district...) and invest in a simple reverse osmosis unit...> The last paragraph is a bit confusing - are you recommending the use of a calcium reactor or adding buffers or both??? <Just the calcium reactor... there are a few major "Beta/VHS" variations here... but (let me whip out my crystal ball here) there is no doubt, NO DOUBT, that the hobby will go the calcium reactor route in the near (next few years) route... the supplement field as it exists now is absolute madness...> Maybe this comes under - too much is definitely not better!! Thanks again, Scott <Be chatting, my sentient friend. Bob Fenner>

Skittish fish We have a 75 gallon reef maybe 2mo. old with a smattering of fish: Chromis, damsels, firefish and a coral beauty. All seems normal but when we do routine maintenance like water changes the fish do a jitter dance in the corners like they are about to be eaten. So my question is: could I put some mirror film on the outside of the tank with the mirror facing the fish so they wont be disturbed? The tank sits in the corner with minimal foot traffic, so what gives? <Umm, if I understand you here... the new water is likely not "ready to be used" as you've prepared it (it's toxic in some way/s)... do read over the "Seawater Use" section and FAQs posted on the www.WetWebMedia.com site... you may need to get a R.O. device (for your cooking, drinking use as well), and pre-mix and store your new/change water for a week or so ahead of use... Don't use a reflective material on the outside of your tank... this will cause your livestock harm, and won't look good to you in any length. Bob Fenner>

Quick question about "top off" water Hey Bob, just had a thought today... You suggested that I premix saltwater and store it for a week or so to get rid of the "gunk" that comes in tap water. Does leaving tap water out in a Rubbermaid container alone make it suitable for top off water too?  Or is there something in the mixing of salt that causes the impurities to go away? <More the latter... the sanitizer (chloramine, its consequent manifestations, chlorine) do dissipate in "just freshwater" from such preparation... many more benefits from pre-mixing and storing seawater> Do phosphates and chloramine and all that other stuff disappear just by "sitting out" awhile? <Not so much phosphates... depending on what format (PO4 doesn't exist in a vacuum... attached and more/less soluble, interactive with other matter depending on... how it is attached/arranged molecularly), but other materials, ionic matter yes. Bob Fenner> Thanks. - Eugene

Quick Water Question Hello Bob, Just wanted to clarify something I read in your newest FAQ, and something in CMA. <Okay> I am now acquiring my equipment for my new 1st saltwater tank (90 Gallon) and starting to plan for initial startup. If I buy a huge trash can, I can fill it with the my salt and tap water, let it sit for a week, with aeration and temp control, and all the bad "stuff" will be eliminated. No need to get RO water?  <Not as much...> No need for water conditioners? (not that I doubt you in the least bit) but just wanted to clarify, reassurance. <No need whatsoever> Thanks again for a great website, all my friends are sick of me talking about my new hobby. I love it!!!! <Me too. Bob Fenner> Warmest Regards, Peter Frederixon

Saltwater storage limit? Bob, I have spent the better part of the night browsing through the Wetwebmedia site. I have been maintaining a 55 gallon saltwater tank for 10 years (okay, I did start completely over after a move 6 years ago), and I am constantly amazed by my ignorance. <I for mine as well> I am constantly procrastinating on water changes because the water making process is kind of a pain for me. I am busy with human children and other pets... Anyway, I did purchase a large Rubbermaid waste container on wheels and an extra sump pump a while back to make this easier. <Very good> After reading your opinions on making up the water, I am almost sold. The drawback--I only need 5 gallons/month for my tank's water changes. Can I make up a whole bunch of saltwater (say 20-25 gallons), mix it for a week, use what I need and store the rest (covered) with no circulation indefinitely? <Absolutely. No problem. Bob Fenner> Thanks, Linda

Shelf life of saltwater Bob, We are purchasing a house about 45 minutes north of our current location and I will be moving my marine tank. I am going to prepare saltwater in advance of the move (at the new location) and was wondering how long mixed saltwater will stay 'good'?  <Many months> Also, should I mix in some tank water a few days in advance to establish some of the bacteria to the new water or is this a waste of time?  <A worthwhile action> (I will preserve as much tank water as possible to avoid too stressful of a situation, hopefully.) Your piece on WWM gave me some helpful information on the process as well. Thanks. <Good to hear/read. Be chatting. Bob Fenner> Humbly, Mike Stewart

Rubbermaid brute Dear Bob: My LFS tells me that some of my reef tank problems might be because of the plastic trash can that I am using for preparation and storage of my RO salt water. I am using a Rubbermaid trash can, but it is not the "Brute" model that I see you recommend. One of the RO manufacturers has told my LFS that the storage container should be "food safe". Do you know if the Brute is "food safe" and is that one of the reasons why you recommend it? Bob Pentecost <As far as I am aware, all of Rubbermaid's products are food safe. The Brute line definitely is... We used them extensively for decades. Bob Fenner, who may send this note along to RM.>

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