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FAQs About Water Changes for Marine Systems 4

Related Articles: Marine Water Change, The 'Perfect' Water Change Regimen? by Scott Fellman, Water Changes, Exchanges by Anthony Calfo, Captive Seawater Quality, General  Marine Maintenance

Related FAQs: Water Changes for Marine Systems 1, Water Changes 2, Water Changes 3, & FAQs on Water Changes: Rationale, Gear/Tools, Frequency/Amount, TechniquesAutomation, Trouble/shooting, & Water Top-Off Systems, Evaporation/Water Make-Up, Treating Tapwater Marine Water QualityMarine Plumbing

Water changes (w/o much change in chemistry, physics) re important for invertebrates as well as fishes.

Re: SW fish mortality... more GIGO, generalizations in, g out. Now water chg. %   7/27/17
Thanks bob. Always wished there were more hard science when it came to this, more in the direction of cat and dog understanding.
<Google the names Andrew Rhyne and Kathleen Wood. These two have been gathering such data>
I will throw one more in there, misinformation, taking ideas from others and thinking they will work for you.
Was just told by someone at a reputable online fish e-ticket that more than a 25 percent water change at a time is harmful and removed beneficial bacteria. I always thought and still believe organic build up in a fish only set up is bad, and the good bacteria existed on rock, sand tank, and very little in the water.
<Mmm; am leery of generalizations... Would require information on how the replacement water was made, how the old water was removed...>
Never heard of too big of a water change in a fish only set up, as long as temp, salinity and other spec param.s are close.
Thanks again Bob.

LA Fishguys, Automated Water Changes        5/31/16
Hi Bob,
The latest of LA Fishguys went on-line last night.
Your promotion is in Part One
Part One https://youtu.be/erAueBrhO_I
Part Two https://youtu.be/ISRonmE2ALY
Part Three https://youtu.be/6IFwt5ExBUw
Part Four https://youtu.be/yMNpwcwpgWo
Jim Stime, Jr
Aquarium Design - Installation and Maintenance
Midwater Systems - JELLIQUARIUM Jellyfish Display Systems
MyFishTank.com - Acrylic Aquariums, Stands and Canopies
LA Fishguys - Aquarium Reality Television
<Thanks Jim. BobF>

Sm./Nano water change frequency    9/18/13
Hello WWMCrew,
I have a nano 'aquarium' (10 litres UK), and I was wondering how often I should perform water changes. I was initially performing one 15 - 25% change per day, but I've read that once a week should suffice?
<I would likely default to the weekly changes... but as a general rule, the smaller the volume, the more frequently I would perform... AND most important to mention; I'd ALWAYS have pre-made water on hand with such small volumes for "emergency" change-outs>
I have one red cherry shrimp (will be adding a few more quite soon).
Parameters are 0 ammonia, 0 nitrite and around 2 nitrate. The ph is 7.6 - 7.8.
<Mmm, I'd bolster the pH (in the change water)... likely to 8.2; with a commercial product... SeaChem's lines are faves here. Reliable, miscible>
Thank you.
Kind Regards,
<And you, Bob Fenner>

Effects on Septic System, SW  8/28/10
First - thank you for creating and maintaining the best site for information on this hobby! I have referred to it for years and always find it to be correct and therefore trustworthy. I have a unusual question - I have recently moved to a house that is on a septic system. I would like to know if the deposits of salt water during weekly water changes (approximately 10 gal.) would negatively effect the system. I researched to find the salt in water softeners do not have enough effect on the bacteria in the system to harm it, but wasn't sure if that would equate to the salt water in a reef system.
<Ten gallons of saltwater shouldn't be a problem here... the amount of salt, diluted by other sources, won't kill your digesting microbes. Bob Fenner>
Any information on this would be appreciated.
Best regards,
Melanie Roberts

Water changes in a troubled reef tank, 3/1/10
Dear Crew,
Thank you for running such a great website and resource for we novice types! This is my first time writing all, so please excuse the rambling.
<No problem.>
I have been searching the FAQs and I am more educated now than ever but I still have a lingering question on water changes. But first, a little background on my tank:
100 Gallon reef, 30 gallons in the sump
ASM G3 Protein skimmer
Magnum 350 for Carbon
4x96 power compact lighting
100 lbs of live rock
Soft corals and fish only. I know my lighting won't support stonies (I would love to though)
2-2.5 inch sandbed
In operation for 3 years, same configuration, bur livestock has changed slightly
1 Hippo Tang, 1 Zebra Tang, 1 Royal Gramma, Mated Pair of Clowns, 3 Fire Shrimp, few red hermits, and a Diamond Goby (the newest addition)
My tank has had a rough run due to many factors. My RO filter is located outside, and we have had horrendous cold weather. Then the RO gave up altogether. Then I stopped doing regular water changes. This is my fault, and now I am cleaning up the mess.
<Not fun.>
I just replaced and upgraded the RO/DI system and changed its' location so that outside temp won't be a factor.
What I am worried about is when I was doing regular changes, it was 1 large change a month (20-25 gallons) rather than several small changes. I have now put myself on a tight regimen of two 5 gallon changes a week (Sun and Wed) and in the past 2 weeks have changed 50-55 gallons in two large changes (once for removal of a ChemiClean application, once to do a full cleaning of the sump). Do I need to worry about taking too much water?
<No, not really. I would avoid doing more the 50% at a time, but otherwise you should be fine.>
Can I do 15 gallons a week?
<Sounds like a good amount to me.>
My tank turned into a hair algae paradise and I want to correct that in the worst way. I don't want to kill the tank in a fit of water changes though. Am I worried about nothing?
<Mostly, there is some risk with large water changes, or even relatively small ones with vastly different water parameters, but I think you should only see improvement from 15-20% water changes a week.>
Thanks in advance!
Phil Aenchbacher
Re: Water changes in a troubled reef tank 3/3/10

Thank you for your quick reply! I have been learning the aquarium hobby for three years now and your site has been an integral part of my reading and learning!
One last quick question before my next crisis: Once this algae recedes I want to add some new soft corals, and polyps (would love stonies, but alas....) but it seems that some (before the green tide) of my polyps died from bad water flow. I have 2 Koralia Magnum 6's (2200 gph) located across from each other, and a smaller Koralia (400gph) for a dead zone in the rear of the tank. Is my placement of power heads just that bad? Is my flow insufficient? I don't think I had any real chemical warfare going on with a stock issue (large) leather, blue and purple mushroom polyps, and a large rock of green star polyps. I tried to make sure nothing got direct flow,
lost a gorgeous hammer coral that way.
<Well I am hardly the coral guy that several of the other crew members are, I just have a few zoos and mushrooms, but I prefer several small pumps/powerheads rather than a few large ones. While total volume of water
movement is important so it how it is moving. Perhaps splitting the flow of the Magnums with some plumbing work would help, rather than just having them blasting all in the same direction. Also, you would be surprised how
much corals can effect each other, my mushrooms can really effect my zoos if I am not careful.>

Water Change 1/20/10
<Hi John>
I have a 30 gal tank that has been running for about 4 weeks now. I gradually introduced 3 fish starting with a Yellow Tail Damsel, to a Ocellaris Clownfish, then a yellow pygmy angelfish.
<Tank is not aged nearly enough for introducing pygmy angelfish and this genus does not do well long term in tank sizes such as yours. "Yellow Pygmy Angelfish" doesn't tell me too much, but the two that come to mind are the Lemonpeel (Centropyge flavissima) and the False Lemonpeel (Centropyge heraldi, both not easily kept
in smaller systems.>
My pH is around 8.0-8.2, nitrite 0, ammonia 0, and nitrate 15-20.
<Nitrates levels in this range are not favorable with pygmy angelfish and are quite high for a 30 day old system.>
When should I do my first water change.
I want to allow the tank to build up but not go too long.
<Build up more nitrates?>
Also how much do u recommend I change. ( I hear about 20 percent?)
<In your system, 10% weekly. Please, in future queries, do cap names of fish, and all pronouns for that matter including "i's".
Do spell out words, no text type messaging please, as we have to correct/edit before posting.
Do read articles and linked files in the headers re above.
James (Salty Dog)> 

Water Changes With No Fish? 6/19/09
Hey guys,
< Hello!>
I love the site! I just have a quick question.
< Well, Ok. Since its just a quick one. Ha Ha >
I've been in saltwater for over a year now but recently I got a new tank.... I've had my tank set up for a few months now (29g BioCube w/30lbs of LR).
No fish just yet, but I do have some coral in there. I've been testing my water every week and every thing comes out perfect, corals are doing very well also.
< Great! >
I'm not really planning on getting fish in the near future, I want to do this right and take my time. Now let me get to the question, if I don't have fish (no wastes being produced) do I have to do water changes every week?... Thanks a lot guys. Mark-
< I'm a believer in water changes. The not only remove wastes (fish & CORALS both produce waste)
but replenish trace elements. Regular water changes are a reefers best friend. GA Jenkins >

Quick Question No Water Changes? 9/13/08 Hey guys, I want to let you know that I appreciate what you do. <Thank you Jon.> Now for the question. I've been arguing with my brother in law about the idea of water changing. He claims that since his levels all test out as good (which I double checked his water with MY test kit and all the levels appear to be good) that he doesn't need to do water changes. <There are other benefits, not just the dilution of what you tested for.> He doesn't see the point in messing up a good thing. His fish are good, haven't lost any in a couple of years. This is also how long it's been since he's done a water change. He claims the water changes were the reason he used to lose fish. What gives?? <All systems will reach a tipping point without water changes, some take longer than others. Regardless of how a fish looks it will be healthier in a well maintained (read: water changed periodically) system. The benefits are too numerous to list here; luckily WWM is a great resource with all of this archived. http://www.wetwebmedia.com/water.htm and the linked articles/FAQs at the top will arm you with the knowledge needed.> Jon <Scott V.>

Question, water changes  9/5/08 Hi! I am a little baffled by one of my customers. They don't believe in water changes at all... They have heard of a friend that has had fish for 40 years and never done a water change. <Nor likely cleaned their carpets...> What do you think about this - if you have any information on how people come up with this idea let me know so I know how to handle my customer.. Thanks. Jim <Have them read here: http://wetwebmedia.com/water.htm Bob Fenner>

Re: Everything going bad 01/24/2008 Thanks so much for the responses. <<Hello, Andrew again, thank you for the follow up>> I broke down and got a R/O system because I got sick of driving to the LFS to buy 5 gallon jugs of water (this isn't a cheap hobby by the way). I've tried to read through the faqs on water for marine systems and I've got some better understanding on how to handle water, but I've still got some questions regarding storage and top off. <<No problem, we shall get these cleared up for you today>> First off do I need to worry about water top offs on a 55 gal tank with sump if I'm doing weekly 10% water changes? Is this eventually going to raise my specific gravity due to evaporation, or will the water changes take care of that? <<Yes you do need to top off the water. If you don't, the Sg of the tank will rise because the water evaporates, but the salt stays behind>> If my SG does start getting away from where I want it what's the best way to bring it back? By adding fresh water, or lower SG water changes? <<If your SG is getting high, then only add RO water to bring this back to acceptable levels>> If I do need to do top offs in small amounts can I just use straight RO water into the sump as long as the temperature is close? Or do I have to aerate, heat and let it sit over night? (I'm trying to build good habits for a reef tank down the road, but I don't want to spend hours each night keeping this thing going) <<As long as the temp is average of the top off water, adding it to the sump in small amounts is fine. Maybe consider purchasing/setting up an Auto-Top off unit>> Second, when I'm "aging" water should I age it as fresh water, or after I've aerated, heated and added salt mix? <<I do it all in one go. I turn on the powerhead and heater, add the weighted out salt to the water, leave for 24 hours. Check levels and adjust over the next 24 hours. Then all is good and ready to use>> Finally, do I only need to aerate 24 hours prior to water change, or once it's been aerated can I store it like that? I'm just trying to come up with a checklist of things I need to do. <<You need it aerated 24 hours at least, I prefer 48 hours personally, before use. This gives the water time to settle, and get to the right temperature and SG to level>> I have a small house and storing multiple trashcans full of water is going to be difficult for me, plus the setup of my RO water system will make it very time consuming to fill the trashcan so I'd like to get enough water to do multiple water changes if possible. *** Kind of like this... ** Run R/O water into Rubbermaid can Aerate with powerhead and heat over night (longer?) Add salt mix to get up to 1.023 (what I'm currently at with FOWLR system) Add buffer as needed Do water change ...store water for a week Aerate and heat overnight Do water change Repeat <<Yes, that sounds fine. I used to be in a similar situation. I had one trashcan ( waste bin here in the UK ;) ) always full of RO water. When it was coming time for water change I would remove the required amount of water to a separate trashcan and add the required salt, mix etc etc. Then store away the can after the water change till next time. This way, you don't have lots of saltwater sitting in a trash can without movement and heat>> Is that kind of right or should I store it fresh after aerating and heating for top offs and only add salt/buffer 24 hours prior to water change in smaller batches. <<See response above>> Finally some non-water questions: <<Oh good>> For my Aiptasia problem they're really only bad on a couple of rocks (maybe 2 or 3 out of 10 or so). If I pulled these rocks and gave them a real good cleaning would it affect the bio filter enough to make a difference? How long does it normally take for dead rock to become live rock? <<A good simple solution for Aiptasia removal is to fill a syringe up with boiling water, and blast the Aiptasia directly, watch it melt. Dead rock to live rock really depends on the amount of live rock in the tank to seed the dead. Can be anywhere from a couple months, to 6 - 8 month, a bit too open-ended to answer more specifically>> What's the best time to treat the Aiptasia with Kalkwasser and scrape algae/bacteria to reduce stress on the fish? Right before/after a water change, far from a water change? At night when they go into hiding? (I forgot to mention this earlier, but one of my gobies ate a big blob of Kalkwasser paste after I was treating the Aiptasia which may have led to his disappearance) <<This will certainly not of helped the fishes stomache..>> Sorry about all the questions. Chad <<Thanks for all the questions, hope this helps. Please shout back if you need some more clarity or more questions. Thanks, A Nixon>>

Water Change Maint.  1-11-2008 Hi <Hello there. Yunachin here> I haven't been good about cleaning up the sand (via the siphon hose) in my tank. When I do it can I recycle the water or do I need to put in new water? <Whenever you remove any water from your tank in the cleaning/siphoning task, you need to replace that water with clean water of the same temperature as your tank. Here are some links to check out in reference to what you need to do: http://www.wetwebmedia.com/water.htm ; http://www.wetwebmedia.com/watchgantart.htm> Thanks <You're welcome! Yunachin> Jim

Water Change Technique 3/15/07 Dear WetWeb Media <Hello> After I got done reading your last answer you sent me. I got to thinking about if I was even changing water and cleaning the tank the right way. I have this question for you. <Ok> When you do water changes and clean the filter sock that I have in my sump, do you shut down the system, meaning the pumps while you do this? <I do.> I hope this is not a crazy question for you. <Not at all.. I just don't know the answer to it 100% I think I'm right but I'm wrong a lot more than I'm right? <Me too.> Because I have been turning the pump off when I do water changes I just thought that was common sense. <Is to me, less chance of burning something out that way.> Thank you for your time answering my 1000's of questions. Jeff <Welcome> <Chris>

Cleaning Crushed Coral  1/15/07 Hi, <Hi, Pufferpunk here> First of all, I love you guys' website so keep it up. <Thanks, we try our best!> Here's my situation:  I have a 150 gallon fish only saltwater tank.  The tank has two Emperor 400s, a 15 gallon sump with a very powerful pump, a protein skimmer, UV-sterilizer, two heaters and two compact lights.  As far as biological filtration, I have about 80-100 lbs of live rock and a 4" substrate of crushed coral.   The tank has been set up for almost two years now.  In the tank I have 6 Bartlett's Anthias, a yellow Coris wrasse and a Firefish (forgot his full name.)   <Nice collection of fish.> Anyway, here's my dilemma:  My substrate is getting completely covered with some form of red algae and it looks almost like a carpet.   <Do a search for Cyanobacteria.> This algae spreads to my rocks but not to my glass. <If it's Cyano, it could take over everything.> I think it looks neat, so I'm okay with it on my rocks but I'm afraid this will stop the biological filtration from my crushed coral since parts of it get completely covered.  Now, my question is: Is there some type of cleaner fish that works well on crushed coral?  I thought about a sand-sifting goby but I don't think most varieties would be able to sift the crushed coral because it is so big.   <I'm always surprised when I see my watchman goby carrying large pieces of rubble & shells, into his cave.> If there is no fish that will clean it, how do you recommend taking care of the problem?  Just vacuum it once a week or so?   <Yes> I've read that it's not a great idea to disturb the substrate too often, because it will affect your anaerobic bacteria. <Not true.  With the kind of substrate you are using, it is recommended to vacuum weekly, to prevent buildup of detritus & nitrates.  Enjoy your great tank!  ~PP> Any information you can give me will help.   Thanks guys, Doug

Water Change  12/21/06 Hi Guys, <Hello> I have a Vision 180 FOWLR setup which I will call Tank 1 and also a 88 Ltr FOWLR tank which I am setting up as a Seahorse/Caulerpa tank which I will call Tank 2. I have set up Tank 2 with a view to farm some food for my herbivores in the Tank 1 set up.  <Ok, but may be some better macro choices than Caulerpa.> I have a question on water changes. Would it be possible to use water from Tank 2 for water changes ? i.e.. Water that has been biologically filtered by the Caulerpa. Process being, drain half Tank 1 water, Drain half Tank 2 water. Put water from Tank 1 into Tank 2 and vice versa. I know this looks complicated but basically I would like a constant recycling process without having to make up RO water on water changes. <Not really, this process will not remove everything that needs to be nor add in important trace elements and buffering agents that a conventional water change would.  Also the Caulerpa is quite active chemically which could have a negative long term effect.> <Chris>

Water Changes VS Water Top off; Apples VS Oranges?    11/27/06 <Hey Clinton, JustinN here today.. No formal greetings? *grin*> I have a 125 gallon tank with 120 pounds of sand and 100 pounds of live rock that is about four months old. The system is mainly all reef about fourteen corals, which are mostly LPSs and a couple sps.   There is also a few fish. yellow tang, royal Gramma, two yellow tail gobies, two small clown fish, Scotts fairy wrasse, and three Chromis.   The chemical water environment  is steady throughout the week with water changes. I was just wondering since the water evaporates at almost five gallons a week if it would  be ok just to do water top offs instead of complete water changes. <I do think you have a little bit of a misunderstanding of water evaporation and water changes. They are not interchangeable. Water top off is to maintain salt density at a proper level, based on the evaporation. Water changes, on the other hand, are used to remove waste from the water (whether they're detectible by tests or not, they are still there) as well as replenishing trace elements and natural balance to the water. Please don't reduce your husbandry skills for this reasoning, if you're that concerned with the maintenance involved with both topping off water, and water changes, set yourself up an auto top off system. There are many commercially available, and DIY projects abound to achieve this end. Hope this helps you! -JustinN> Thanks a lot for the helpful information.? What about the formal greetings? <Simply that all correspondence through our site is posted, archived for all to see, and we tend to like a more formal, proper form. It tends to make things easier to identify and follow. The comment, however, was meant in jest and not intended as anything more. -JustinN>

Re: Q Tank Size -- Now, a follow-up   11/24/06 Hi Bob!, <Hey Q, JustinN with you today> More of a comment here than a question (though I will sneak a question in towards the end!) <Hehe, ok> Following the advice and good reviews on this site, I replaced my Red Sea Prizm protein skimmer with an AquaC Remora. <An excellent decision, IMO> I received the unit about 1 week ago, gave it a quick cleaning with warm water and set it into my tank.  I was a little nervous at first because the unit was not producing any skimmate at all.  The bubbles didn't seem able to make it even half way up the neck of the collection box...  Having read (here) that these units require a "break-in" period, I shelved my concerns and sat back to wait.   <Always a good idea with a new addition, equipment-wise> After about the 3rd day of operation, the skimmer appeared to suddenly kick into action, producing a large volume of organic laden bubbles.  With some minor tweaking (I was very familiar with making tiny adjustments after my aggravating experience with the Prizm) <I know this all too well, am awaiting the arrival of my Tunze DOC 9002 to replace my Prizm as well...> I had the skimmer producing a nice dry foam that resulted in a good volume of dark skimmate... Much more than I'd ever seen from the Prizm. <Excellent to hear> Thank you for the great advice. <Hehe, wish I could take credit for this one *grin*> What do you think about the twice a week, small volume (5%) water change regime outlined in detail on your site?  because I've noticed that my fish seems to react positively to a water change, I was considering going with this 'system'.  Would you vacuum the substrate every water change?  (this is not covered in the article).  Will this be stressful to the fish? q <I agree wholeheartedly with the sentiment of twice weekly, lower percentage water changes. I utilize a 3-4 gallon water change, twice a week in my 40 gallon aquarium. Usually, I don't disturb the sand bed unless there's a need. Instead, I use a small powerhead for water change purposes. My storage container sits next to my aquarium, with the pump laying in the bottom for circulation. I attach aquarium tubing to the pump, then place the pump in my display. Using the hose and flow from the pump, I start by blasting my rockwork clean and getting the gunk into the water column. Next, I direct the water out of the tank into a bucket for disposal. Then I simply toss the pump back into the storage container, and return the water to the tank. I see no reason that this would be stressful to the fish. Hope this helps you out! -JustinN>

A Grab Bag of Questions... Water changes/SW, UV use, Sponges as foods   11/19/06 Good evening WWM crew, hope all is well. I have a few general questions for you, if you don't mind. First off, a good number of aquatic-veterans agree that, in most properly planned and maintained systems, smaller, more frequent water changes are more beneficial than larger, less frequent changes. I was reading Scott F's article on doing 5% water changes twice a week, and was wondering if it would be just as good, better, or worse to do 1 or 2% daily water changes? <Mmm, possibly... the ideal would be to continuously change out a bit... as in dripping in/out> Most of the information on daily water changes that my search turned up referred to emergency situations and medicated tanks. I currently live in an apartment and it would actually be easier for me to mix up a quick <Ahh... better by far to pre-mix, let age... per WWM...> 2 gallon (tank is 90g) batch of saltwater. And by "easier" I mean that my girlfriend does not like the idea of having a Rubbermaid trashcan full of water in the living room. <Can be located elsewhere... pumped or bucketed...> I'd estimate, three weeks of daily changes a month, and one week of a single 10% water change so I could actually have time to vacuum the gravel. Any thoughts or downsides?? <Time, trouble, spilling... mostly> Tank will be (still in the planning process) a 90g FOWLR system, with a canister, skimmer and maybe a UV sterilizer, (see next question.) I'm only picking out 4 or 5 medium sized fish as Bob, Anthony, and others suggested in various FAQs for this size tank. So, no major worries about the stocking level. My second question is... Any idea how a UV sterilizer would impact tunicate populations in a tank? <Mmm, possibly reduce available foodstuffs... are filter feeders...> I was given one as a gift, and figured I might as well hook it up, but was curious/concerned about its possible effect on the free-swimming young of tunicates. <Oh! These will likely be readily removed by skimming, predation... if produced at all> My concern stems from the fact that I would like to put a medium size angel in, and want there to be some live food available. I love the Apolemichthys genus, <Will very likely consume ascidians...> and it's not too hard to find retail specimens eating prepared foods in my area. <You are fortunate here> But even if it's eating, I'd like to provide the most complete diet possible. The sterilizer takes a 9watt bulb and suggests 100 - 200gph for most applications and I think around 50gph for parasites. I would prefer to hook it up to my canister's output at 350gph, because in all honesty this would make it much, much easier to clean, service, etc. Is it even worth bothering at that flow rate? <Yes> I know that the extra head (it's a "turbo-twist") will decrease the gph a bit, but I doubt enough to meet ESU's recommended flow rate. Also, on the general subject of feeding angels, is there any real risk to using most forms of "tree sponges" as feeder sponge for angels?? <Mmm... some... many of these... oh I see you address this below> Any concerns about toxicity or decay?? <Yes> I have a small 36"x18" tank I'm using to culture rock that I could quarantine the incoming sponge in. I've read the warnings about most types of "ball sponges," but haven't heard the same caveat about "tree sponges." If there are any major risks with "tree sponges," is there any decent type of sponge to use as a feeder, or is best to just rotate old live rock out and new live rock in? <This last is more... preferable. Oriental food stores may be able to supply you with useful Poriferans... in dried formats> (Shouldn't be a hassle with the extra tank.)  Any ways, thank you again for your help, this wonderful site and your contribution to the hobby. <Welcome. Bob Fenner>

Vacuuming Gravel 10/12/06 Thank you for your prompt response.  I presume to begin the suction you need to suck on the end of the hose? <Can, I use a turkey baster to start it, few other methods out there too.>  Also, how do you heat your small tanks?  I recently added a 7.5 watt heater to my tank but after having left it overnight it doesn't seem to want to heat it above 76 degrees.  <Can the temperature be adjusted?  If not may want to get a different model.>  I'm not sure what temperature unheated water is so I was wondering if this is hot enough. <Ok, a little low but stability is more important than exact temperature for fish.> I know Bettas prefer temperatures in the 80's. <Ideal> <Chris>

Water Changes While Away 9/27/06 Hey guys... have a quick question for you. <Sure>  I have a 29 gallon reef with a 15 gallon refugium with some live rock, and a nice big soccer ball size of Chaetomorpha underneath. <Nice>  I have a small hand full of small corals I can list them if you need, I have 2 clowns, a fire fish, and very very small red line angel.   My question is this.  I am in the military and am deploying for just round 30 days to the middle east. <Good luck and please be careful.>  I usually do 15% water changes every week and am usually very on the spot for the husbandry of the tank.  My problem is I really don't have anyone that I can trust to do water changes and siphoning while I am gone. I can have my brother feed them because all you have to do is get some tank water and thaw a small chunk of the frozen food and feed the anemone a cut up silver side 2 times a week. <Make sure he also knows to top off with fresh water when necessary.>  I will be gone 30 days with a max of 45.  Could I go the max 45 days without a water change? <Probably, but obviously no guarantees.>  Or possible just try and train my little brother to come over and do 1 larger one half way though the month?   <If you think your brother can handle it, I would pre-mix a couple of buckets of salt water and have him make a couple of 5 gallon water changes.  Otherwise it might be worth trying to find a service company and pay them to do a water change or two for you, but depends on cost.  Otherwise your tank will probably be mostly ok, may have some algae problems but otherwise ok.   Make sure your brother does not overfeed, maybe feed half as often as you normally do.>    Thanks <Anytime and be safe.> <Chris>

Water Changes/Stress Do water changes promote stress in the fish? <Should not, more beneficial than anything.> My Porcupine puffer always freaks out after I do a water change and just sits on the bottom motionless for hours, is this normal? should I worry? I always think that he is going to die. I have a 175 gallon fish only and I usually change 75 or more gallons when I do the change. thanks for the help. <Geez, how large is your tank.  Depending on the frequency/amount of the water change, it could cause some stress. If your tank is 150 gallons, and you are changing 75 gallons once a month, and pH is not adjusted to match tank water, some stress can result.  Much better to do a 10 percent change weekly, or a 20 percent bi-weekly, and adjust pH to within .1 of the tank water. James (Salty Dog)>

Water Changes...Natural Or Artificial Seawater   7/18/06 Hello, <Hello James> I am building a new tank with a volume of 1017 gallons <Yikes!  I'm jealous.> not including displacement.  I only have 12 fish totaling about 60 inches.  This is a very under stocked tank.  I will  have aqua medic skimmers running   as well.  I was doing a 10% a week water change on my previous 300 gallon tank.  Is 10% a week still necessary for the new tank with   it being so under stocked?  If not, what would you recommend? <With your present condition, 10% monthly would be fine.> My fish being happy is the number one thing for me.  I like to check each fish and look after them, rather than having loads of fish that   you don't get attached to as  much.  I want them to have loads of space. <That they will.> Also, most of the people here in Cape Town are using real sea water but I am still using salt/ro water mix.  Does real sea water harm the   system or is it safe enough to  use?. <Not a good idea, read here.   http://www.wetwebmedia.com/seawater.htm> Kind Regards, <And to you.  James (Salty Dog)> James.

Exposing Corals During a Water Change - 07/06/06 Hi crew, <<Hello Deb>> I have what might seem like a silly question, but I need to know so here goes. <<Only "silly" if you don't ask...so ask away!>> If you have corals in your tank and they are high in the tank and can't move how do you change a significant amount of water, say 25%, if that will unsubmerge your corals?  Is it okay for them to be uncovered by water for any length of time? <<See, not a silly question at all...I have done what you describe many times over the years.  Your corals should fare just fine if briefly "exposed" during a water change. A couple things you can do to help ensure they will remain fine are... If you have any corals with large-fleshy polyps you should "gently" coax them to expel their water/retract.  This will prevent the weight of the water in the coral's flesh from causing damage once buoyancy is lost due to the receding water line... You can also turn off your lights to reduce the amount of heat the corals will have to deal with while exposed.  And don't be alarmed by the presence of excess mucus once the corals are "rehydrated" as this is a normal response to exposure to the atmosphere>> I just haven't seen the answer to this and know I will have this dilemma soon because my corals are somewhat in the upper part of the tank and changing  1/3 to 1/4 of the water would uncover them for the time it takes to finish taking out the old water and getting the new back in. <<Not to worry Deb...is not unusual for many of the corals we keep to be exposed to air in the wild during periods of low tide>> Also, I am having a hair algae problem and have bought several critters that are supposed to eat the stuff including turbo snails, large and larger, a blenny, and a pretty big sea hare.  None of them seem to find the hair algae at all interesting. Is this unusual? <<Not at all.  More often than not this is what happens.  I'm afraid there are no "magic bullets" (or magic critters) for dealing with hair algae.  Biological controls are always "hit and miss" as you have discovered.  Best to try to determine the cause and attack the problem from that perspective.  Please do have a read through our data on marine nuisance algae.  Start here (http://www.wetwebmedia.com/avoidingalgaeproblesm.htm) and also follow the many links at the top of the page.  Much info to absorb>> I have an opportunity to trade the sea hare for another one.  Is it possible that the new one might eat the hair algae even though the big one doesn't. <<Is a possibility, yes>> The snails aren't interested in it either.   <<As far as snails go, the large Mexican Turbo is probably your best bet.  You mention a blenny but not which species...blennies from the genera Salarias and Atrosalarias will be your best option for dealing with your hair algae>> Thanks, Deb <<Quite welcome, EricR>>

Quality nano vacuum/s   7/2/06 Hi, I've got a six gallon nano tank (saltwater) and was wondering if you guys know of a good quality, battery powered vacuum. <Mmm, this is sort of a "conflict in terms"... that is to say, most all such battery-operated vacuums are not of very high quality. However, the best of these are made by Eheim (not easily found in the "west", but can be had...> I want one that will  clean debris from the sandbed and can also be used for water  change siphoning. <Mmm, will need two for these tasks... I'd get a smaller diameter "regular" one (Tetra has some smaller diameter ones that you can still find about) for the latter purpose> I've been surfing the web and have come across many  different types/brands but I can't tell which ones are of  good quality. Can you guys point me in the right direction? Thanks, and  happy reefing, Greg   <Glad to proffer my opinions here. Have used many makes, models... the Eheim and Tetra manufacturers are excellent. Bob Fenner>

Siphoning/Cleaning Marine Substrates - 04/26/06 I have been reading over emails for a while and I finally found what I was looking for, but not the complete answer. <<Ok>> I read that in a reef tank, if you have crushed coral then you should siphon during a water change. <<Mmm, maybe...depending on depth of the substrate (<1")>> If you have fine sand, you don't need to siphon. <<More at play here than grain size/depth but generally yes, with good water flow the finer grain sands are lees likely to accumulate detritus>> Well, we have a 72 gallon tank with 3.5 inches of an even mixture of sand and cc. <<Mixed opinions on this...should be fine>> Should we siphon and how deep? <<I wouldn't disturb the DSB, but do some reading up on deep sand beds here ( http://www.wetwebmedia.com/deepsandbeds.htm).  If detritus settling in/on the substrate is of concern then "up" the flow in your tank to keep all in suspension>> A greenish/brownish layer is starting to form about halfway down and I don't know if I should disturb it. <<This is algae that is triggered by the available light coming through the tank front and likely does not extend very far in to the sand bed...nothing to worry about>> Also, since I am here, I have 50 lbs of live rock in the tank.  I will be adding 50 more lbs that I have had in a separate tank for a month.  Is this going to change all of the parameters in the tank initially?  I just wanted to prepare myself before I see any spikes in my tests. <<If the rock is fully cured it should not be a problem though having water handy for a water change after the move (disturbing/stirring detritus) is a good idea>> Thanks, Chris <<Cheers, EricR>>

Holy Moley-Yes Folks Aquariums Need Maintenance To Function'¦'¦  - 04/19/06 Hello, <Hi Dan.>      I have very high nitrate levels in my 55 gal. tank. <Uh-Oh!>   Can I get rid of these levels by using a combination of Aquarium salt and Cycle? <Huh? No'¦'¦?   I don't want to, but if I have to I'll do the water changes, <What? Not wanting to do water changes. Sir, excuse me if I sound bold but if you don't have the time to do at least weekly (ok maybe bi-weekly)'¦.then you should not own any type of aquaria.> the only question I have about the water changes is...How long do I wait after refill to start again, assuming I will need to do more than one water change to bring the levels down? <Read WWM re Water Changes for your answers my friend. I will say a few consecutive daily water changes (10% to 25%) over the next week.> Thank You, <Mmm-hmm.> Dan C. <Adam J.>
Re: Holy Moley-Yes Folks Aquariums Need Maintenance To Function..  - 04/19/2006
I'm sorry I didn't mean I don't do the water changes at all, what I was saying was if I have to I will do the rapid water changes.  I read where you can reduce the nitrates in the tank rapidly by doing a 60% reduction, filling it back up to 80% capacity, then doing a 40% reduction, filling it back up to 100% capacity, then doing a 20% reduction and again filling it to 100% capacity.  This is the water changes I was talking about,  I own two tanks and have had them quite awhile, so I'm very careful of my levels in both tanks. <Okay, sorry for the confusion. I don't like to perform LARGE changes in one swoop, I would perform 25-30% water changes, but do about 5 of them, one a day or one every other day over the course of the week or two. Also find the root problem that are causing these nitrates to be so high.> Dan C. <Adam J.>

Water Changes/Marine/Continuous Water Changes   2/26/06 Hi WWM,<Hello Jason.> Everything I have read regarding water changes in marine systems indicates that smaller, more frequent water changes are better than larger, less frequent ones (all else being equal, of course). <Agreed> As an engineer, this leads me to wonder if a continuous water change system would be even better than small, frequent, discrete changes. What I mean by this is a system that slowly but continuously adds new saltwater (from a separate mixing container) to the main system and drains existing water to a waste sink (container or down the drain) at the same time. This could be worked out to match the average change rate of 10% per week, more or less depending on tank size, inhabitants, etc. <Such water changing devices are available.> Do professionals make use of such open-loop systems? <Most do> Do public aquariums use the ocean as a source/sink in this manner? <Yes, aquariums near the coast practice this in an effort to cut down operating costs.  The Boston Aquarium for one has their saltwater intake about one mile offshore for purity reasons.> Thanks for your thoughts! <You're welcome.  James (Salty Dog)> Jason
Water Changes/Marine/Continuous Water Changes   2/24/06
Hi WWM,<Hello Jason.> Everything I have read regarding water changes in marine systems indicates that smaller, more frequent water changes are better than larger, less frequent ones (all else being equal, of course). <Agreed> As an engineer, this leads me to wonder if a continuous water change system would be even better than small, frequent, discrete changes. What I mean by this is a system that slowly but continuously adds new saltwater (from a separate mixing container) to the main system and drains existing water to a waste sink (container or down the drain) at the same time. This could be worked out to match the average change rate of 10% per week, more or less depending on tank size, inhabitants, etc. <Such water changing devices are available.> Do professionals make use of such open-loop systems? <Most do> Do public aquariums use the ocean as a source/sink in this manner? <Yes, aquariums near the coast practice this in an effort to cut down operating costs.  The Boston Aquarium for one has their saltwater intake about one mile offshore for purity reasons.> Thanks for your thoughts! <You're welcome.  James (Salty Dog)> Jason

Water Changes - 2/21/2006 About how often and how much should I change out of a 30 gallon marine aquarium with an Ocellaris pair, a Pygmy Angel, and two blue-green Chromis? <<While I think a 30-gallon is too small for the Angel, I would change 5-10 gals every week.>> Thanks for your help, <<Glad to help. Lisa.>> Mike Lushbaugh

Water Change and Adding New Fish  - 2/21/2006 To Whom this may concern, <Hi there, Leslie here with you today> I just change my salt water tank on Friday 02/17/06. The  water is cloudy and not healthy for my maroon clown fish, it also kill my coral reef beauty angel.  Do I have wait for the tank to recycle again or it is safe to restock new fish in there? <I always like to wait a few to several weeks before adding fish to a tank that has had any sort of problems. If your tank cycled properly initially you should not have to wait for the tank to recycle after a routine water change. However since you lost a fish and the water is cloudy I would suggest you test your water for Ammonia, Nitrites, Nitrates, pH and Specific Gravity. If the tests are all fine it should be ok to add a new fish after a few weeks. Quarantining new fish is always recommended to help minimize the risk of introducing disease into an established healthy system.> My maroon clown is in an emergency tank ( 20 gallons ) right now and looking healthier. Glad to hear your clownfish is looking healthier. Please do keep a close eye on him and the water parameters in your 'emergency tank'. If that tank is without biological filtration you will need to be doing daily water changes.> Thank You, Mickey <You're very welcome, Leslie>

Water changing systems I have recently been given a 400 gal. aquarium by a friend of the family. <Lucky you.> I have been reading about setting up new aquariums and could not pass up this opportunity. The aquarium has everything that is needed  and is running now. It even has a wave machine. <Great> The gentleman had it set up as a reef tank and lost most of his livestock after the FL hurricanes. My question is what is the best way to do water changes in a tank this large. He has it piped into his house and sewer system. I would like to start it as a reef/fish tank. Is this a good idea? <Yes, do read on requirements/needs/maintenance, etc on our web site.  As far as water changing, a tank this large is going to require about a 30 to 40 gallon change per week.  I'd go with an auto water changing/top off system.  Here is a link to one you can read about. http://www.drsfostersmith.com/product/prod_display.cfm?pcatid=13959&Ntt=auto%20top%20off&Ntk=All&Ntx=mode+matchallpartial&Np=1&pc=1&N=2004&Nty=1  James (Salty Dog)> Thanks, <You're welcome> Steve Edmiston

Hydrogen Sulfide - 01/01/2006 Happy new year to you all, <And to you Will.> This weekend I had the pleasure of stripping down my 60(UK) gal marine tank for the 2nd time, what a way to end the year but with a nice slow leak...? Anyway all the rocks corals fish etc. are in a nice spare tank set up with heater, filter, skimmer, and sand is in a vat with water and a powerhead. However my sandbed seems to have been producing hydrogen sulfide instead of nitrogen, kind of lucky the tank leaked in retrospect. The sandbed is about 4 inches deep I should imagine, maybe a little under, I have a bout 240lph of flow through the tank <excluding skimmer>. What's causing the hydrogen sulphide? Bed too shallow? Not enough flow? Wrong bacteria proliferating? <Anaerobiosis, organic build up. Flow must be leaving dead areas.> And other than the smell what effects does this substance have? Suppressed pH or is it actually toxic? <Hmm....Being from lack of oxygen, the pH would be depressed, could have a random "die off" of all livestock.> FWIW soon I shall be upgrading from a Prizm skimmer to a v2skim 400, will this help problems, the Prizm never really does much <other than irritate the family with it's gurgling and bubbling> <Will likely help as will better flow. Good surface turbulence will help gas exchange.> Thank you in advance, Will <You're welcome. - Josh.>

Water Changes and Adam's Discipline  12/10/05 Bob, <Actually this is Adam J responding Bob is out right now. I'm responding now so that you know your query was received, I will respond now but will also place this aside so he can respond later as well.> We would like to know if you would give us a quote for the following:  When making a water change in a marine aquarium: How often and what percentage should be changed? <This is highly variable depending on the set-up but personally I prefer at least 10% weekly at a minimum for stability.> What's the rule of thumb and can we put your name as the person quoting it? <Well personally I'm not a fan of 'rules of thumbs' of any kind, simply because there are far to many variables. Some systems are understocked some systems are overstocked. Some systems are big some are small. Some are shooting for a zero nutrient level some are shooting for a slightly elevated nutrient level. However if I had to limit myself to one statement on water changes I would say, 'As with anything water changes should be preformed with discipline. Plan out a routine that keeps your system stable and meets its needs and don't vary from it.'> Thanks <See here as this may answer some more of your questions: http://www.wetwebmedia.com/scottsh2ochgart.htm.>_ Eric <Adam J.> 

The microscopic world, speculations on FW, SW "Dead Sea" effect  11/15/05 Hello again, <Hi there> Jonathan here. Have acquired an Observer III microscope to help me diagnose fish problems where I work. Both of the fresh and the salt. <Another world awaits you> I can do 40x, 100x, and 400x. I'll be getting another eyepiece so I can do 600x for that just a little bigger than 400x. <Mmm, much larger> I've been making dark field / oblique filters to try and see what I see. <... I, not "i"> I don't want to invest in phase contrast just yet, unless I find out there's no other way. Have you ever gotten decent resolution for searching for parasites at 400x with a dark field filter? <Yes> I have to use oblique by slightly moving my filter holder out alignment. That and sometimes giving myself a headache by closing down the iris aperture all the way.  I'll be getting a mount for a digital camera, so that I may attach it to the scope. May I send you an video for feedback? <Yes> I may make a website to share my progress with others. <Outstanding> I'll keep learning where I am, and try and take a course at my college to refresh my technique. I might have an opportunity to attend the diseases of warm water fish seminar in Florida. Do you think it would be an improving experience? <Yes> Or that by working in an aquarium store that I'll eventually see most of what they would show me. <Oh no... a very good idea to have both experiences to draw from> Two recurrent problems, which may even be related, in salt; is possible Brooklynella running loose and cloudy eye. CopperSafe is at half dose continuously. Brook is said not to be affected by copper sulfate, which would make sense. The way it looks on the fish is very much the description in books and internet. Have scoped a few scrapes, but I'm too new to say "that's it".  I'm taking action against it, but victory is not yet reached.  [course of action is freshwater baths sometimes with Meth blue 7 -15 min.s every 3 days about, but return to the same tank. I can't pull a clean tank out of the air, <...? But you can buy a scope?> and by corporate all tanks need to be full, ha. I could shut off a tank from the central, remove the copper, and hit it with Rid Ich+, which I'm considering, if my bath approach is not getting results..] <Shotgun approaches are not encouraged> Would it be possible that ich or velvet could be present in the gills of new fish at such a level to cause death without being present at all on the body & treating at half dose of copper is not enough to solve the problem? <Yes... a therapeutic dose is just that... less than is more harm than good> Its a possibility I just recently considered. I think if I see encysted ich or velvet on a newly introduced fish, its probably just temporary. Until it falls off divides and the copper kills the free swimming stage. Cloudy eye I think is caused by our water. Most things I read linked it to environmental issues. Our nitrate is barley registering on our Jungle Quick dip stick, as accurate as that is. I think we may be exporting nitrate by scrubbing algae, and removing and drying out Cyano infested crush coral substrate.  <Your speculation is worthy> So that nitrate would not be an entirely accurate judge of the water quality. Only doing 30 gallons out every week or two, may not adequate in a 900 gallon system. <Uh, no> I think we actually evaporating and topping off more than we are taking out and replacing. I've noted this on a discus tank we had by using a TDS meter. The TDS value was much higher in the tank than the source water like 3 - 4 times. <Like potted houseplants, these tanks need periodic large water change-outs to dilute solids...> Even taking account whatever live plants died or bogwood adds, it gave me a way of showing the problem. Ha, the TDS wouldn't work in saltwater, its over its limit. If hypothetically this we evaporating and replacing say 75 gallons a week, and only did a 30 gallon water change a week. Could this lead to problems?   <Yes> Wouldn't over time the whole of water become more mineral rich, and with all the contaminants of the tap. This might lead to a cloudy eye problem.  <Agreed> Too much contaminants, too much minerals, too much bacteria supported by those. Any ideas?  I've tried to keep this short. Sorry and thanks, Jonathan <Do please learn to/use your spelling and grammar checking tools... a good learning experience. Bob Fenner>

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