Re: Tap Water and Phosphate   2/23/07
Thanks for the response Mich!
<You're welcome Dave!>
So basically, tryout some bought DI/RO water in a few water changes... And if it's working, then invest in a unit.  
<Yep!>
Never woulda thought to buy the water first.  
<Sometimes it's the obvious that isn't so obvious.>
Thanks!
<Welcome!>
Re: Diving... Yes, the small critters are certainly cool to look at...
<And take pictures of!>
But some of these big fish will certainly get the blood pumping.
<Are we an Adrenaline junkie?>
It's an interesting experience.
<Mmm, interesting wasn't the first word that came to my mind!  Hehe!  Better you than me my friend!  -Mich>
Dave

RO/DI water...   11/8/06
My pure water coming from my DI reads 0 ppm on my TDS meter.  I have a new 32 gallon garbage can in my basement that I am putting the water into and pumping it up into my sump, then into my tank (Brand new system, 125 gallon reef ready). The tank is directly above my water in the basement. It still reads 0 in the garbage can, but when it gets into my sump and then to my tank it reads 115 ppm.
<...?>
  I have all new plumbing (pvc), and has sat done for over 2 weeks, all shavings were cleaned out.  Why would my ppm be 115
<... a lot of dust in the air?>
when it is pumped up into my sump, and is there any way I can get it back down.
<Run it back through...>
  Is that a really high #.
<Nope>
  I have 2 AquaClear powerheads circulating the water now.  
Also when I add salt to the water will that effect the ppm at all.
Thanks
Aaron
<Yes... adding any solid that will go into solution will increase TDS... Bob Fenner>

What would you do?  An experienced point of view needed please. When in doubt, your own R.O.   8/23/06
Hello crew,
Need help here as soon I will be using my current 84 gallon tank as a quarantine and graduating to a 480 litre (English measurements) tank as my
main one. I have been using R.O water on my smaller tank and of course everything has much improved especially my phosphate and nitrate and no
doubt my fishes health too. I would like to use the R.O water on my soon to be new tank but financially it would appear that it may be more costly than I first realize.
<Mmmm>
I understand that with larger systems the nitrates etc tend to rise slower therefore sometimes requiring less frequent water changes,
<Mmm, depends on what's in them... how much... what fed... what filter gear employed... mostly>
perhaps once per two weeks or even once only per month in some cases?
<Yes>
I may end up buying an R.O unit,
<I definitely would here>
my LFS are hoping to strike a deal with someone where the units will drop from about 100 - 150 to about 50 - 90 £.
<Look to the large hardware, "home" stores here... there is nothing "exceptional" re the "fish store" units and the ones meant for home/potable use>
This, though, will be a few months away. Attached to the mains drinking water I have a very high quality ceramic filter. Perhaps as it was quite
satisfactory for my small tank it will therefore be even a little more acceptable for my larger tank when it arrives?
<... Worth having the resultant water quality checked... I would get/use my own R.O. unit if there were any prominent issues with your/my source water... for pet-fish and my cooking and drinking needs. Bob Fenner>
Kind regards team.
Steve.

RO Water  - 09/14/06
Hi Crew,
<Mr. C>
I have a couple questions about RO water. For a simple fish and  invertebrate system, with a couple of hardy corals, is RO water really  necessary?
<Mmm, nope... depends on what your source water is, what otherwise you want to do...>
I feel it might help out a bit. For again, a simple fish and  invertebrate system, would 3 stage RO be fine, or do you NEED the 4th stage,  deionization?
<No>
Would my system survive if the 4th stage is not provided, and well  water is used?
<Very likely so>
I talked to a fellow hobbyist and he said he believes using well  water with a RO system would be better than city water because it doesn't  contain all of the chloramines and such. Is this true?
<Unless one is adding chloramine...>
Doesn't well water have  more minerals though?
<Not all... too many vague generalities here... There are tapwater's that are quite mineral laden, and relatively soft wells>
Also, what brand of RO filters would you suggest for  someone who has a
fairly small (36 gallons) system?
Thanks a ton!
<A cheapy Home Depot or equivalent unit. Bob Fenner>

Water Softeners
Hello! 
I love this site (so much information!) but I can't seem to find the answer to my question. Exactly WHY are water softeners (the kind that uses salt exchange) not recommended for freshwater tanks? I have a friend who I have tried to warn against this but she won't accept just "it accumulates chloride ions"....and sometimes I wonder too....(here's the dummy part....we are talking about salt right?) because if you're using the water for water changes, you would be removing as much as you are putting in, right? Not good I'm sure for top offs, but otherwise wouldn't the levels stay the same? And if this is true, then the salt level in your tank couldn't be that high could it? Around the same level as people who use the teaspoon of salt per gallon thing? 
Thanks for taking the time to explain this!! Barbara 
< Ok here goes. The resin in water softeners uses the sodium (Na+) ions in the salt (NaCl) to exchange with the Calcium ions (Ca++) in the water. So now you water is not as hard but now it has lots of sodium which is not good for fish. To truly soften water you do need to remove the calcium and magnesium ions with a reverse osmosis unit that removes the hard water ions by forcing the water through a membrane that only allows the water molecules through and leaves the others behind. Another method would be deionization. The water runs through a two types of resins that attracts both the positively charged and negatively charged ions leaving essentially neutral water. Distilled water uses evaporation to leave the ions behind while it condenses into pure water. If you just added tap water all the time without doing water changes then the minerals in the water would accumulate and become higher than the water source, unless they were utilized by plants. This is an over simplification but this is how it works.-Chuck>

Need RO Unit? 
Bob Fenner, 
<Stephanie> 
I have a quandary that I'm hoping you can help with. I cant seem to get a straight answer on whether or not I need to consider an RO Unit for my tap water. I'm keeping mostly Clown Loaches (about ten 4" guys and one 9" - 10" guy) and 1 relatively large (about a foot long) Arowana in a 135 gallon tank. (As an aside, My husband is toying with the idea of starting a discus tank, not that our tap water is conducive to discus at all. But that's not my current problem). The clown loaches I've read can be very sensitive to water quality. So I finally was able to get a hold of a consumer confidence report from my local water company. The measurements I am going to rattle off here are the highest levels found: 
PH 9.3 <Yeeikes> 
Nitrate 4.23ppm <Yowzah, out of the tap?> 
Nitrite .02ppm 
Hardness (as CaCo3) 246ppm 
Sodium 59ppm 
Sulphate 23ppm 
TDS 384ppm 
Aluminum 1024ppb 
Chloride 139ppm 
Arsenic 1.2ppb 
Barium .13ppm 
Copper .09 ppm 
Lead 10.7ppb 
<Umm, you are indeed a candidate> 
I've also attached a copy of the water report, in case I'm not reading this properly. But after looking at those numbers... (if I'm reading it correctly) I'm really feeling like I should be getting my butt out to the local Home Depot and getting an RO unit for my fish. But all the LFS keep telling me its an unnecessary expense for a freshwater tank. Can you please give me your opinion, it would be greatly appreciated!! 
<If it were me, my source water I would at least "blend" some treated water (and likely reverse osmosis would be the technology employed)... and mix, circulate the new water a good week before using (in a dedicated plastic trash can...), AND I would utilize the RO water source for my drinking, cooking uses. Bob Fenner, whose wife's family are from northern NJ and have great potable water> 
<<NJersey Water Report.pdf>> 
Thanks, 
Stephanie Koll

Tap water quality improvement
Hi Robert, great article on water quality.  I'm just getting back into marine aquaria again and have a question regarding water. As usual, water here in Victoria B.C. Canada is chlorinated, no surprise here !  Would a 3 or 4 stage reverse osmosis system solve problems with chlorine and other crap for a marine fish tank water changes ?
< An RO unit removes almost all the minerals from water including chlorine. It is so pure that you would have to add everything to make it a complete saltwater mix.-Chuck, Sorry, Bob was unavailable to answer your question.> 

Abbreviations (6/20/04)
Awesome, thanks for the advice, I plan to use it. <You're welcome.> Sorry for the stupid question, but what does RO, and DI mean? <Not stupid at all.> I'm sure it'll be obvious once I
get the answer, but I saw on the website and message below, but have never heard before. <RO=Reverse Osmosis add DI=De-ionized; The DI is a further step after RO or a method by itself that leaves the water even more pure than RO. Using strictly DI wastes no water, while RO wastes 4 gallons or more of water for every gallon of purified water produced, depending on how bad the water is to start with. Much more info on WWM water FAQs. Steve Allen.>

- RO vs. DI -
Hi, hope all is going well there.  Please clarify something for me.  I had planned on getting a Kent's "bare bones" R/O unit, but recently read that if water is only R/O treated and not R/O AND D/I it can still cause problems in the aquarium. <Is this specifically related to silicates? If so, the presence of these is often overrated and blamed for Cyanobacteria outbreak. Problem algae can be avoided by means other than source water, especially if the silicates are reasonable.> Please let me know what you think. <Really depends on the quality of your source water. RO/DI will leave your water stripped and demineralized and then the water will need supplementation to make it suitable for saltwater - for instance adding buffers. If and unless your tap water is complete junk, RO usually does the trick.>
thanks, James
<Cheers, J -- >

- Bare Bones RO -
Hi, I have a 75 gallon F/O tank.  I am considering buying one of the Kent Marine Bare Bones R/O units.  Please tell me if you know anything about them. <Yes, I know a thing or two about them... was there a specific question?> Also, I have never owned any kind of R/O unit.  Are they hard to assembly and/or use? <Should come out of the box ready to use.> thanks, James
<Cheers, J -- >

- Bare Bones RO, Follow-up -
could you tell me if they are a good quality product? <For the most part, the majority of RO membranes are created equal. You will get good performance from this unit.
Cheers, J -- >

- Bare Bones RO, More Follow-up -
I have read that if water is only purified through a R/O unit and not a R/O / DI unit, that the water can still contain impurities. <Is one way to look at it.> Please explain. <Please read here: http://urila.tripod.com/ and here: http://chemistry.about.com/library/glossary/bldef52900.htm > I also would like to know the difference between R/O and D/I. <Read up. Cheers, J -- >

Do I Really Need an RO/DI Unit?
Hello.  I am new to saltwater but have had freshwater tanks for around 5 years now.  I have found that my tap water is just not cut out for saltwater in that my tanks  (72 gallon and 18 gallon) turned pea green literally overnight within a week and a half of each other.  I have tested the water with ammonia, nitrate and nitrite all at zero.  My pH is 8.3, salinity is 1.023.  In researching your site, I found only one post that referenced something called an Omnifilter and it was made in passing.  I have purchased an Omnifilter system and the filter cartridges that I am have are a string wound whole house filter that is rated at 5 microns (first in line) and a carbon filter that has a rating of 2 microns (second).  I am wondering if filtering my tap water through this system will take care of getting rid of the chlorine and chloramine for use in my tanks without the use of a dechlorinator. << I'm not sure, but to me, using carbon is good enough for chlorine and chloramine removal.  Also, if you let the water sit out after the filtering for 24 hours, you should be fine. >>  My thought was to try to reduce the amount of silicates that are in my tap water and increase the quality without going to a full blown RO/DI unit. << I think that is a good move.  Obviously RO/DI is a great way if you can afford it.  Keep in mind many many many people have great looking tanks with tap water.  However, they also have great filtration and lots of corals. >>
Michelle Peralta
<<  Blundell  >>

Confused About Water
Hi Crew,
Thanks for the work that it takes to maintain such a great site. I am only asking a question because I'm still confused over the water used in water changes. I have a 46 gallon reef tank with only soft corals (mushrooms, xenia, leathers). Before I had any coral in the tank, I used tap water to do my usual 6 or 7 gallon change every two weeks. I try to get 25% changed per month. However, since adding coral to the tank, I now purchase RO/DI water from my LFS, which is a pain. I mix the water with salt in two 5 gallon buckets and add it slowly to my sump. This was fine, but recently another area LFS told me that somehow RO/DI water becomes ¡°unstable¡± after a certain time and that city tap water (properly buffered and dechlorinated) is a better approach.
I have no idea what ¡°unstable¡± means.
<Me neither... maybe ask for some specifics from whoever is stating this?>
Another friend who maintains systems around my area had the city tap water tested twice with no copper or phosphates. He personally keeps a similar size and type reef tank, and does so very nicely.
Despite all this, your site suggests RO/DI units for reef tanks, but maybe only the larger systems?
<Mmm, to be more accurate, RO/DI is suggested for localities with suspect source water... that is laden with nutrients, possible toxicants as you state above... Many places the tap water is fine... pre-mixed and stored, aerated and heated for days... a week or two ahead of use. You may well be in this category>
Some responses state that water you can drink may be fine for a marine system.
<Yes>
Is tap water without copper and phosphates, yet buffered and dechlorinated suitable for a reef system?
<Likely yes>
Are there some trance minerals in tap water harmful over time if allowed to build-up?
<Almost never... these minerals are "traded out", diluted along with all else during water changes>
What am I missing in this water change process?
<Mmm, doesn't appear much>
And given all the
information from all these sources, how should I care for my corals and fish?
Thanks for your time!
-Mike
<Sounds like you're doing fine Mike. Most important element in your success is an open, curious, discerning mind... You seem to have this. Bob Fenner>

Aquascaping / Pump / RO-DI / Rock 7/21/05
Real quick (depending on your perspective), a few unrelated questions in relation to planning a step-up from a 20 gal. to a 90 gal. w/ sump)
1.  Is it a bad idea to stack rock directly on the sand bed (obviously, having the typical uncovered bed area in the tank front) in terms of structural integrity (since the bed slowly dissolves, etc.), or would it generally be more advisable to either have the rock  placed on the bottom with sand filled in thereafter around the rock (which I did on my 20 gal., but that seems to require far more rock to obtain nice elevation) or have the rock basically supported independent of the sand via a pvc structure (with the first stackable portion of the pvc support layer being maybe an inch or so under your sand top)?
<Best to not set directly on substrates, but either on the bottom or other structure that is stably resting on same>
Am I making too much of the dissolution of the sand in relation to the integrity of the overall rock structure?
<No, not IMO... have seen some real trouble from the effect of this dissolving... is more of an issue than most all aquarists realize... A bunch of carbonaceous material does go into solution... and differentially... That is to say/warn, that folks ought to add to theirs, perhaps take some out and replace after a year, then every half year or so going forward>
2.  For an external return pump from a sump (let's say, for the sake of argument, an Iwaki or PanWorld), is it ok to have the pump sit parallel to the sump as opposed to perpendicular?  By parallel, I mean the pump is connected to the sump with completely straight plumbing directly into the pump, whereas by perpendicular I mean having a short piece of pipe exit the sump, hit a 45 degree angle and then hit the pump (you probably gathered this without my elaboration on "parallel and perpendicular";)).
I would like the to do the later for space saving purposes.  I'm guessing that one turn won't cause much grief in terms of flow to the pump intake, particularly if the sump output is a 1 inch hole graduated down to the pumps intake of 3/4 inch.  Thoughts?
<Not a big deal either way... of course, given there is no reduction in fitting, plumbing on the intake side>
3.  In general, and in terms of say "typical" city water (realizing "typical" is a loose, indefinable term), will I gain much benefit from using an RO/DI unit vs. simply an RO unit?
<Most source waters, no>
  Maybe I'm wrong, but long term it seems as though an RO or RO/DI unit will be more economical than a DI unit alone (such as the Kati/Ani unit (unless you try to reconstitute the filter media, which sounds like a major pain in the rear), a Tap Water Purifier (I've used this on my 20 gallon since the tank requires modest water changes and top-off).  
<You are absolutely correct here. Reverse osmosis is the cheapest, easiest means>
I think I read in the FAQs by Steve Pro or someone that the small Kati/Ani unit that sells for about $139 can knock out about 200 gallons of purified water (high cost per gallon), and my little Tap Water Purifier can knock out about 30-35 gallons at somewhere around $13 to $15 dollars a filter.  Under those scenarios, and absent trying to renew the media, the little old Tap Water Purifier is more economical than the Kati/Ani unit.  Anyway, I digress.  Do you feel an RO or RO/DI unit will long term be more economical, all things considered, than just using DI units?
<RO>
How do you feel about the current line of RO/DI units by Kent and Spectrapure?
<These are fine... know that they're actually not "made" by these companies...>
Lastly, for a 90 gallon tank, what minimum flow rate for such a unit (i.e., RO) would you advise?
30gpd?  60gpd? 90gpd?
<Even five, ten gpd will do... given storage of the water... I have a small unit for my pet-fish use>
I know that the higher the flow the harder your DI at the end will work as more will make it though the RO, but it seems like a 30 gpd unit will be painfully slow in producing water, particularly if you don't have it plumbed into an auto top off / reservoir fill-up scheme (i.e., just brewing water as you go).  I mean, if a 30gpd unit is really about 24gpd, that's obviously a gallon an hour.  How slow is that?!?
<Mmm, not very... really... the oceans were made more slowly...>
My little DI unit can spit out up to 10 gallons an hour....
4.  Lastly, my 20 gal. has some rock in it which has been the subject of a hair algae battle from time to time.  Would it be a mistake to introduce that rock into any part of a new system, even if in the sump or refugium?  Under what circumstances might you make use of this rock, if at all, in a new system?     
Thanks for your time.
<I wouldn't be dissuaded from using this rock... the "local" conditions... light, predators, competitors, water quality... dictate the life, demise of the algae... Bob Fenner>

High Mineral Content
High mineral content in my tap water.  What is the best thing for me to do to remove it?  I have tried a phosphate sponge, but there are no real directions and I don't know if I am using too much, too little....<I would not use the phosphate sponge. It has never worked for me. My advice is to buy RO (reverse osmosis) water. Or if you want to save a lot of money purchase an RO unit yourself.>
I started this because I have TONS of red algae in the tank... it's still not gone.   I am afraid of doing anything too drastic because I don't want to shock the fish.<agreed, I would not use your tap water any longer.>  Can you please help. <Do read more about RO water on our site or search Google. IanB>

Silicate Situation...
Hi Purified-H2O Guru:
<Well, I consider myself more of a high silicate source water victim! LOL...Scott F. at the keyboard tonight!>
I really don't want to RO my tap water as it is pristine, above 8.0
straight out of the tap, and full of hardness (good for marine tanks, bad for everything else.)
<No discus for you...>
No copper, lead, iron or other nasties ... even chlorine is so low it's almost usable without Amquel-nuking. But, silicates are around 70 ppm...which may or may not be fueling diatom blooms in my tank.
<Yep- they are! I know whereof I speak on that one!>
I have 2 questions :
a.) Isn't natural sea water around 2000 ppm of silicates (or of silicon specifically), and therefore adding 70ppm is only increasing this load by about 3.5% ?
<Mathematically correct...But in a closed system- silicates from source water can spell a nasty diatom plague...RO/DI is the way to go, my friend....Preferably, a unit with an extra silicate membrane...>
b.) Is there a product that will remove just silicates and leave everything else alone?
<Well, there are silicate "removing" products and resins, but they are both expensive to use on a continuous basis, and unreliable. Really a better move to go RO/DI with a good unit, like a Kent Marine "Hi S" model, or a SpectraPure 5 stage unit...Initial investment is high, but they pay for themselves down the line in terms of media replacements and frustration! Good luck! Regards, Scott F>
Thanks, SLC

Misguided Advice on How to Use RO Water - 8/10/03
Hi All, Hope all's well,
<with hope for you in kind>
I wondered if you would mind answering a few questions for me, I have spent the last hour reading FAQ's and am getting a little frazzled! I have a 36"x12"15" reef tank, set up at the end of last summer, lightly stocked, lots of live rock.  Stats:0 Ammonia, 5 Nitrate, 0 Nitrite. Canister filter, Berlin Skimmer, well aerated, lots of current.
<if this is a reef tank... do allow a small amount of nitrates to linger else the corals will starve and/or have poor color. Seek up to 5ppm on your test kit (nitrate-nitrogen).>
I have been having a few problems, namely pH fluctuating from 7.83  to 8.31 during the course of the day.
<Yiiiiiiikes!!!!!!!!!!>
(Big mistake buying a digi meter!) Alkalinity is 12 DKH, Calcium 380. As well as we have been having a bit of a heat wave over here and the tank temp has also been moving 4-5 degrees over the day!!.
<ughhh!>
(Too small tank that is the result of not doing enough research and listening to the guy in my local fish store)
<understood>
I tried to rectify the pH swings apart from making no difference I managed to raise the alkalinity up to about 25+..! .brains!!..have none!!
<staggering <G>>
Needless to say my corals are not looking healthy.
<glad to hear some are still living <G>>
Mushroom coral shriveled, Mushroom Anemone very closed . Xenia closed, Pulse Xenia, ..not pulsing and looking decidedly grey!. Fish seem fine!! phew! After a few major water changes, things seem to be settling down although I fear might lose some corals.
<you are on the right track... large water changes to bring you back to par>
Anyway now for the good news!!  After finally realizing I will never have a stable 3ft tank I have purchased today a 48"x12"15 tank and am in the process of setting it up and trying to remember all the things I should of done when I first set my tank up last year! I have had the tank drilled I plan to use the three foot as a sump, with maybe an overflow type filter system, in combination with the canister filter,, not too sure yet. Hopefully at the end of it I will have a more stable system! , fingers crossed. (any suggestions )
<hmmm... the larger tank is nice, but it really is not so much bigger as to correct your water chemistry problems... that is a matter of husbandry>
Anyway the question really is your opinion on the pH fluctuating. I do 10% water changes weekly...using RO
<hmmm... hoping the RO water is first heavily aerated (24+ hours to raise the pH and drive off carbonic acid/CO2) then re-mineralized (buffered) and mixed (12+ hours) and only then considered for use as evap top-off or salted for seawater). Else you have a source of your pH instability (weakly buffered source water)>
I am in two minds whether to continue using it. My LFS has their pH at 7.8 using RO and there corals seem fine, perhaps larger more stable system?.
<7.8 is irresponsible IMO for reef inverts. Seek a proper 8.3-8.6 soundly.>
However I went to another LFS store and they have the most stunning reef tank, around 6 foot, by 3 by 5, and they use ordinary dechlorinated tap water? I could not believe it.
<not surprising... the matter is not RO vs. tap water... it is simply about using stable and quality source water. For some folks, that is right from the tap... for others the reconstituted RO water is necessary>
All they have is a large skimmer and a trickle filter Am I missing something here , I fear I am.
<the trickle is no help (unless there is a huge fish load) and in most cases is a harm (excess nitrate contributions). One or two good skimmers on the tank is crucial for most systems though IMO>
I have also been told that continually using RO water, could lead to a collapse in the pH?,
<you are being advised by folks that have no concept of the dynamics of water chemistry. Properly handled RO or DI water (back to aerated, buffered and measured before use) is a tremendous boon to reef-keeping. It offers very stable and consistent source water (of known comp).. unlike the best tap water which fluctuates seasonally if not weekly>
and that I really should use 2/3 RO and 1/3 tap water, what is your opinion?
<get better local advice <VBG>. Ha!>
Anyway sorry for the waffle I am sure I will have some more questions for you buy the end of the weekend!
<really no worries at all. You will do fine being so inquisitive... keep reading/learning my friend>
Cheers for you help Rob. UK
<with kind regards, Anthony>

RO/DI Unit
Hello WWM crew!
A couple of questions; I'll try and make them as quick as possible.
1.) My tank has had some down time. I was having a terrible time with hair algae and got fed up with it and just left the tank alone for almost 4 months now. I didn't have an RO/DI unit and I think that my source water was the culprit. Now that I am making a little more money and have the means to get the right equipment I will be purchasing a Spectrapure 2000 65gpd unit soon. I've done no water changes during the down time and the tank looks like crap! I am planning to clean the algae off the glass and take the rocks out, scrub them off as best I can and add more substrate. 
<sounds like a plan> 
( I only have about an inch and a half avg. depth ). I'll put the rocks back in and rearrange them. When I do this I want to make a large water change. <ok> Can I use distilled water as a substitute until I get the RO/DI unit and then do another large water change? 
<you could but I would just use regular tap water with some dechlorinator added to it> 
Should I just wait and use RO/DI? 
<I would just use tap water for now until you get this> 
Do you think that the algae will begin to die off after I replace most of the tank water with RO/DI water? 
<depends... on how much you feed your fish and the dissolved organics in the aquarium>
2.) I need to upgrade my circulation system as well. I plan to buy a pre-made sump and use an Ampmaster 3000 as my main circulation. I think that I can plumb this pump into numerous returns and still have adequate water flow. If not I'll get the 3500. I do not have a drilled tank. I was thinking of getting 2 CPR 1600gph overflows to feed the sump. What are your opinions on this idea. Any other suggestions besides having the tank drilled ( that's really not a feasible option )? 
<I would get the two CPR 1600 GPH pumps>
I hope that I did not confuse you on the first topic! Hope to hear from you soon. I will definitely have more questions for you as I am planning to renovate the majority of my system. 
<I look forward to it>
Thank you,  Stephen Baker 
<you're welcome, IanB>

RO water? 11/4/03 
I have a 75 gal with a DIY 20 gal Eco-system sump/fuge. This is a brand new system and I am getting ready to fill'er up but with what type of H2O? 
<Deionized is best. And with any purified water, be sure to aerate and buffer for a couple of days in advance> 
I have city water that is sediment filtered (not sure to what micron size) then it passes thru a water softener and thru a charcoal filter to remove chlorine. Is this water safe to mix with a synthetic salt or should I make a investment and buy from the marine LFS pre-mixed RO saltwater at about $1.00 a gal , or purchase a r/o unit? 
<I'd recommend a 2-column deionizer instead like "Kati/Ani columns".> 
My softener is essentially a deionizer. 
<not correct my friend... you have an ion exchanger... not a deionizer. Two very different things. Using salts to soften water makes poor quality water for aquatic life for the imbalance in exchanged ions> 
Would this water be ok to use? 
<nope... better to actually take your chances with tap water> 
I currently use potassium in my softener instead of salt, could this be a problem. 
<yes> 
I wouldn't think so since the softener just uses the potassium or salt brine to recharge the resin bed with negatively charged ions. 
<and leaves residual chlorides that accumulate and skew the alkalinity pool/water quality. I have seen tanks crash in time (less than 18 months) because of this> Kevin Velleca 
<best of luck. Anthony> 

Water Softener 1/4/04
Hi guys, Hope you had a great new year
<Hi Chris.  Adam here.  Same to you!>
I live outside of the city and am on town water...all water that comes into the house is filtered through a water softener
What should I be doing if anything to compensate for this when completing the water changes on my 110 salt FO system
What I have been doing in the past, is turning off the water softener and letting the tap run for a while in an effort to get the softened water out of the system...
Should I continue this practice in effect working to get the hardest water possible or should I just allow the softened water to enter the tank... Let me know
<Water softeners work on ion exchange.  The ions in your city water that are responsible for the hardness (Ca++, Mg++, CO3-) and for scale production are exchanged in the softener for Na+ and Cl-.
Over a long period of time, this could cause a slight imbalance in your tank water (more from top-off than water changes).  Regular partial water changes should help minimize this effect.  Adding an R/O unit to filter the already softened water is the ideal solution.  It will remove most of the NaCl, and the softened water is very gentle on RO membranes.
If an RO unit is not an option, I would probably use unsoftened tap water filtered through a carbon block/sediment filter.  If you choose this option, please do get a water analysis from your water company to be sure that Phosphate and metal concentrations are acceptable.>
thx Chris
<Our pleasure!  Adam>

- RO Questions -
Hi Bob,
<Actually, it's JasonC today.>
Hope you're doing well.  Can't help it, gotta say it again. Great Site! Many of us are in your debt, I'm sure.  I have a few questions if I may.
First the vital stats:  Setting up and will/do have  75 G, will be reef setup aiming for corals, a few fish (2 or 3 is fine with me, as I like corals equally as much if not more).  Haven't quite decided on models, but will use a wet/dry sump, probably removing bio-balls at some point, 75-100 live rock, and good skimmer. <If your plan is to build a reef tank, how about starting the system with the bio balls out...> I have NO plans to skimp on quality and will decide what I need first, and worry about price later.  I'm in no rush with all this.  I'm having a lot of fun planning and reading. <Good.>
1.  Where is the article for the "Reverse Osmosis Water Purification"?  The link seems to show a blank page.
http://www.wetwebmedia.com/h2opurifiers.htm <It's a reminder for those of us that work here that the article needs to be written. Perhaps you will do that for us??? Might I offer a link [with an article] that might help on the subject:
http://www.wetwebmedia.com/water4maruse.htm ><<It's 9/30/06 and still isn't done... sigh. RMF>>
2. I know I need some sort of RO as two friends in my area swear that it was the only way they could keep marine life (bad water here apparently). I will take their advice of course, but I'm a bit confused.  What is the difference between DI and RO?  From the FAQ, it seems to me that in the end, they accomplish same thing, one just does it cheaper than the other. Am I right?  Also, there seems to be some dissension with the folks on your site as which is better, DI or RO.  Is it really just a matter of preference as far as overall water quality is concerned? <Hmm... you are pretty much right on most counts. Typically RO systems have at least one, sometimes two pre-filters which protect the RO membrane from larger particles. What comes out at the end of the filter is very clean water. Some RO units also have a DI[onization] filter that is after the RO unit to further purify the water leaving the RO. Depending on just how bad your water is... you may find this necessary, but for most purposes RO is sufficient. Likewise, you can obtain a filter that is loaded with both resins that attract both positive and negative ions - the Tapwater Purifier is a popular brand - that can do a pretty good job, but the resins tend to exhaust themselves after a while, and the filter needs to be replaced. In the case of combined RO and RO/DI filters, the actual filters tend to last a little longer because they work as a group rather than individually.>
3.  Is the HD/Lowe's units really just as good, <Yes.> and is an RO/DI an RO/DI <Yes.>, or will the staff at these places need to know that I'm looking for one that will be appropriate for Marine Aquariums? <As far as I know, there are none of these filters specifically for Marine aquariums - they are just water filters.>
4.  I'll take your advice and mix in containers first, but for the experienced friend that volunteered to help, what should I tell him when he asks "why not mix right in the tank".  Honestly, I can't think of a reason why it would hurt. <Because it doesn't always mix so well like this... you end up stirring up the sand, etc.> Also, if I do mix in separate containers, wouldn't that mean I would need something like 3, 25 gallon containers? <Yes, although you could do it over a couple of days. I like to use the 32 gallon Rubbermaid trash cans.> Seems excessive for something I'll need once (If I'm lucky ;-) <Use Murphy's law as a guide and keep the trash cans around... you may find that you need them all one day.> Am I looking at this the wrong way? <Not really, but if money is not a concern of yours, then plan for the worst with redundancy.> Also, how long can water sit before it goes bad. <Many factors... if you keep a pump in the mix-vat circulating the water and an air stone as well, weeks, months perhaps.> I know that probably sounds like a silly question. <Not really.>  (I'm guessing it must go bad at some point)? <Without circulation and aeration, the water can go bad in a number of days if the ambient temperature is hot enough.> i.e.- How far ahead can I make it, and leave it in the container(s)? <See my answer above.>
Whew!  I think that's it for now.
I'm happy to say I just installed my (empty) 75 G reef ready Oceanic, with stand and canopy, and I must say, it looks beautiful already!  Imagine how nice it will look with life in it ;-)
Take care, and thank ahead of time.
Yours truly,
Eric N.
<Cheers, J -- > 

Re: RO/DI.....do I have to?
OK, so the idea with RO/DI is to keep from adding potentially harmful substances to the tank, causing algae outbreaks, etc. <Right> But in a FOWLR, if I test the source water for ammonia, nitrite, nitrate, phosphate, copper, and iron, and of course use a dechlorinator, since it is FO, couldn't that be alright?   I can't get my hands on any more RO water for a while.  Be honest......thanks.<Honestly, if parameters are in line, should be ok :) see here for more http://www.wetwebmedia.com/water4maruse.htm Don>  
Matt

RO / DI water
Hi guys,
<Hi Brian>
>Wow, I am amazed at how much there is to this hobby, I find it very interesting, just when I think I have read enough to determine an answer to my problem, there shows up a whole other set of questions.
<Join the club, Dude! You should have seen MY questions today! It gets better and better!>
I have a new reef setup, 2 ½ months old and been using purified tap water (well water) for top-off and water changes.
<How is it purified? A Tap Water Filter (DI?) or ?>
The brown diatom algae is very discouraging and looks awful.
<Oh yes, esp. at about 2 1/2 mo.s! Even with great water it can happen in new set-ups.>
I have added various snails, a brittle star, a goby, extra powerheads (helped the most) and still no luck.
From what I have read it is probably due to nutrients in my water.
<Most assuredly so!>
I have a Remora skimmer driven by a Eheim 1250 pump, so I think that is fine, I do get a lot of darkish/greenish skimmate. (55gal tank, 65lb LR, 50lbs fine sand).  I was just about to purchase a RO/DI system until I read about just DI as well as Kati & Ani (hard to find lots of info and products for this).  I already have a sediment filter on my main pipe coming into the house, it would also be very easy to add a carbon filter.
<Ah, more for chlorine, taste, smell, etc. for drinking.>
Do I really need a RO system?  I see that Bob only suggests RO, but Steven and others only use DI or RO/DI.  I am not sure what to do, from what I just recently read, I believe my problem is from silicates and only need DI not a whole RO/DI system.  What is the difference? Why use of RO only, if it doesn’t rid of silicates? Confused again.  Thanks for any advice you can give, I need a clean tank!  Brian
<No worries, test your water for these contaminants, like silicates, phosphates, nitrates, etc. then match your pre-filtration treatment to your water. RO with the right membrane removes up to 99% or so silicates, but DI removes the remaining (assuming you are using a silicate removing resin). So, for most situations, a simple RO works fine. Some of the guys don't like RO because of the water used to produce pure water (a ratio of about 3 to 1 waste to product) where DI units including the Kati/Ani systems have no waste water but require recharging of the resin media when exhausted, as do DI cartridges.  DI cartridges last quite a while when used behind an RO membrane to remove the majority of contaminants. RO is very slow, depending on the size unit, where Kati/Ani will be much faster. All of these things plus expense then come into your decision.  Hope this sets you straight!  Craig>  

- RO/DI -
Hi guys,
<Hello, JasonC here...>
I am amazed at how much there is to this hobby, I find it very interesting, just when I think I have read enough to determine an answer to my problem, there shows up a whole other set of questions. <I find that life is this way.>
I have a new reef setup, 2 ½ months old and been using purified tap water (well water) for top-off and water changes.
The brown diatom algae is very discouraging and looks awful.  I have added various snails, a brittle star, a goby, extra powerheads (helped the most) and still no luck.  From what I have read it is probably due to nutrients in my water.  I have a Remora skimmer driven by a Eheim 1250 pump, so I think that is fine, I do get a lot of greenish skimmate. (55gal tank, 65lb LR, 50lbs fine sand).  I was just about to purchase a RO/DI system until… I read about just DI as well as Kati & Ani (hard to find lots of info and products for this). <DI[onization] is the same as Cation and Anion removal.>
I already have a sediment filter on my main pipe coming into the house, it would also be very easy to add a carbon filter.  Do I really need a RO system? <You may... you might consider having your water tested to be certain.>
I see that Bob only suggests RO, but Steven and others only use DI or RO/DI. <RO gets perhaps the largest portion of... shall we say, 'bad stuff'. Personally, I own an RO/DI.> I am not sure what to do, from what I just recently read, I believe my problem is from silicates/phosphates and only need DI not a whole RO/DI system.
What is the difference? <In my opinion, the DI filter at the end of the RO/DI chain just get's the stragglers... RO filtration is more than adequate.> Why waste all that water and use RO only if it doesn’t rid all of silicates? <The waste water issue is a non - if you are concerned, you can save the stuff and water you garden with it or whatever you deem necessary, but if you drive your car anywhere, those pollutants do much more damage than the water you would waste creating RO water. Most RO's do get rid of silicates... it's just marketing mumbo jumbo.> I would like to just buy 3 clear filter housings, link them together and run 1 carbon with 2 mixed bed filters (same as Kent’s Deion 200 but much cheaper) is this a good idea? <Sure... it really all RO/DI filters are.>
Confused again… thanks for any advice you can give, I need a clean tank!
-Brian
<Cheers, J -- >

Filters and RO/DI
Hi guys hope you are well. I need some advice again please. I currently have a 100g reef tank with live sand, live rock, and a Fluval 404. I have recently purchased a 125 g tank with a 20 g sump. Should I get rid of the Fluval 404 and can I utilize instead by making new salt water mixes and top off water? Do I have to have a RO/DI filter?
<Hi Werner, the Fluval is a great piece of equipment, if you keep it clean.
Personally, I am kinda lazy and would not give the device the attention it needs so I don't these types of filters. I would think it would work well in the new mix solution. Or, you could use it as a carbon only container.
<As far at RO/DI, I would have the source (tap) water checked to see how far out of whack it is. Then if there are high concentrations of stuff you don't want, use the RO/DI (or just DI, higher output/less waste).
Hope the helps, Don>
Werner

Copper in the water 5/14/03
Hi I got a list of what is detected in my water from my water plant they said there is .023ppm of copper is this an acceptable level I have kept my tank for 2 years here with no signs of die off from my corals? Thanks JM
<there is the very real danger of such contaminants accumulating in living tissues ever so slowly over time. Please do not admit any copper in through your source water. Simply filter it over PolyFilter before using for evap top off or making seawater. Best regards, Anthony>

Subject: enquiry to marines?
Hello Robert,
I am newcomer to saltwater marines. I would like some advice from you.
<Study business! Wait, you mean re aquariums>
After keeping tropicals successfully for four years, I thought I would take the step.  Basically I purchased a R.O unit, to ensure better water quality... do you use R.O. units, do you make a saltwater mix yourself?
<We use R.O. for drinking, cooking water... I only keep African Cichlids presently... they get straight (liquid rock, Southern California) tap water>
And do you have any tips for me?  Fish selection as it is a fish only tank. Regards Stuart.
<Umm, yes... study. Maybe start by reading our selection pieces, FAQs... see here: http://www.wetwebmedia.com/MarInd3of6.htm Scroll down to "Selection"... and Read on! Bob Fenner>

RO Water
I worship your wisdom. I must admit I'm on your site quite a bit and have learned a lot. I thank you. I tend to follow your (and Calfo w/corals) recommendations. I do weekly water changes(5 gals for a 45 tank). I have been adding corals w/ success (so far) and would eventually like to have a maxima/crocea clam, leaning more towards the crocea. I am fearful I may not be able to suit its needs. I have 250MH and 110PC lighting. I add calcium (Kalk) strontium and very little iodine via drip overnight. My testing has been pretty good, Cal around 400, PH 8.2, ALK 12.5, very low if any nitrate, etc., also very stable in PH/ALK readings. Phosphate and Chlorine is my concern. My tap water-straight form the faucet-has .17 phosphate level. I seem to obtain a .3 to .6 in the tank. I'm waiting on a chorine test so that is questionable. 
I use Chemi pure, Polyfilter (it's a tan /yellow brown color when in need of change), and an Aqua C Remora skimmer. We pay for our H2O and RO wastes so much. Barry at ClamsDirect stated he highly rec.s RO/DI for clams. Do you think I could get away with just a 2 stage from home depot? My husband already complains about the time I take between the tank and you (site). I presented the RO issue to him and he does not want to waste the water etc. I read your facts and realize I do need to consider chlorine and possibly other pollutants I can't test for but any suggestions from you would be highly appreciated. Sincerely, Sharon 
<Sharon, the company that produces the PolyFilter also has a cold sterilization system with no waste water. You might want to do a search on that. I'm also thinking if you had a 10 gallon tank and ran your makeup water through a hang on power filter with a Polyfilter pad for 24 hours, I would certainly think any pollutants would be removed from the water including phosphate. James (Salty Dog)>

RO/DI Follow-up - Problem Solved?
THANK YOU, I did not know the two stage filters waste water too. Yes, the waste water is the problem. I am going with the 10 gal w/ poly filter and I'll get a filter for the faucet like Pur/ Brita. THANKS AGAIN 
<You're welcome. James (Salty Dog)> 

Phosphate and nitrate removal
Hi, 
<Hello>
I understand there is a filter available for treating new water and goes by the name of NITRAGON or similar can you please tell me where I can buy. Thank You 
<I haven't heard of it, doesn't mean it's not out there. Personally I think you would be wasting your money. I'm assuming "treating new water" means your top of water or water for water changes. In that case, you would be further ahead buying a R/O unit. James (Salty Dog)> <<... http://www.google.com/search?sourceid=navclient&ie=UTF-8&rls=GGLD,GGLD:2004-27,GGLD:en&q=nitragon+filter RMF>>

Nitrate Levels After Reverse Osmosis?
Are there nitrates existing in r/o water ? If so how much? And, is there any way of ridding nitrates before putting r/o water in your tank? 
<Nick, if your membrane in the R/O filter is good, your water should be 97/98% pure. I would do a nitrate test of your tap water and see what the nitrates are out of the tap, if any. I would concentrate on getting the R/O filter working properly rather than incur extra expense in removing nitrates from R/O water. Nick, in future queries please watch your caps and abbreviations. It does save the editor work as these queries have to be corrected before they can be placed in the FAQ's. Thanks in advance. James (Salty Dog)>
Thank you 
<You're welcome> 

Nitrate Nightmare
Hi WWM Crew!
<Scott F. here today!>
I have a 55g FOWLR, 120g FOWLR and a 20g tank that is currently without fish but running. I have had constant problems with  high nitrates in all three of my tanks.  I recently changed from buying  water from my LFS to mixing and storing my own salt water. I store and  mix the water in a 30g trash can with 2 powerheads constantly running. I haven't yet, but I also intend to add a heater.  So far I have only been using the container for makeup water, so on my first run of using it for a water change, I mixed the salt and Amquel and let the water aerate for 2 days before doing a water change.  Immediately after doing a 20g water change to my 120g tank, I did a water test that indicated the nitrates were high in the tank.
<May be in part because of high nitrate present in source water, but also possibly due to husbandry. Do re-visit your maintenance procedures, feeding, skimming, etc., to make sure that these factors are not contributing to the problem. Fortunately, these are easy to correct!>
I have the Saltwater Master Liquid Test Kit that uses a color chart for readings, so it's very hard to tell exact numbers, but let's just say it read that the nitrates were fairly high. Anyway, after realizing that the nitrates were high in the tank, I tested the stored water.  I realize that I should've tested it before doing the water change, but I'm learning as I go.  : )
<Hey- at least you're testing! That's great. Don't be so hard on yourself!>
I found that the pH level was low, so next time I will buffer the water to bring it to 8.2.
<Good procedure>
I also  found that the nitrites were high
<Bingo!>
....this is where my query comes in.  My thinking on the issue is that by using Amquel to get rid of chlorine and ammonia, the ammonia is converting to nitrite during storage and then to nitrate in the tank.  Does this sound logical?
<A very interesting theory, but I'm inclined to believe that the fresh water was high in nitrate to begin with, and certainly not helping the existing nitrate situation in your tanks. When you're starting out with source water that's, say, 5ppm or more nitrate, you're "behind the eight ball" already!>
If so, what can I do to remedy the problem? If this explanation doesn't sound right, what do you suggest?
<I'd recommend that you invest in a good RO/DI unit that can produce virtually pure water at a modest cost. This way, at least you can be assured that you're starting with good source water>
Seeing that I have 3 tanks, it got to be quite cumbersome getting saltwater from the store, so I really want to learn to mix my own water.
<Agreed- been there- done that!>
Does this sound like a problem that a chemical tap water purifier could fix or is an RO/DI unit in order, or is there something else that I'm missing?
<Nope- as above- an RO/DI should help. But do investigate husbandry, maintenance, etc. to help reduce nitrate levels in your tanks.>
Thanks in advance for your help.  You guys are the coolest!
<Not as cool as our readers! Keep up your efforts at learning and improving your systems! You're doing great! Regards, Scott F.>

Re: Water Question... "What is Soft/ened Water"?
I have a fundamental question that I can't seem to get a good answer to.  I currently live in a house with softened water.  I am aware that such water is unsuitable for aquarium use,
<Why... as in what is it in your understanding that leads you to believe this?>
but I have no unsoftened water readily available.  This issue is why I tore down my last tank a few years ago.  I am now researching the feasibility of a new aquarium and would like to find out if softened water can be made suitable again.
<Softened... as in/by ion-exchange resins? So?>
I am willing to buy an R/O unit... but can not find out conclusively whether R/O will make softened water usable again.
<Mmmm, it won't...>
Is it simply the sodium content in softened water that makes it unusable?
<No... not to most all aquatic life>
Does that mean it is usable in a marine tank but not in a freshwater tank?
<Shouldn't, doesn't matter in either case>
I am still considering my options and have not decided whether to go fresh or salt, so I would appreciate an answer/recommendation for both.  What general advice would you give to those of us stuck with softened water?
<Uhh, enjoy, use it...>
Thanks for your help and the great web site!
<Why at least H.S. level chemistry and physics s/b compulsory... There is nothing "wrong" with "softened water"... only a degree of hard water (calcium and carbonate hardness principally) removed... and all plus reconstituted with the use of synthetic salt mixes... Check your source/tapwater from an "outside" tap at home/work, wherever you are... this is very likely not "softened" and can be combined, used singly to start with as much of your TDS (total dissolved solids) as you can get... to start with... Study and don't worry. Bob Fenner>

Parasites and Spring Water
Good afternoon, Need your help again.
<Scott F. here, ready to assist>
I have 65gal salt water aquarium, the first 3-4 months no problems. Last month or so having fish dying with parasites on them, green dust type algae growing on the glass. The only thing I have changed when I do my water change once a month I have started to use bottled spring water. When I first started cycling the aquarium, I filled the aquarium with tap water and then added proper amount of Aquar plus. Do you think my problem is with the spring water I am using? If so, what type of water should you be using. Please reply. Thanks Rob!!!!
<Well, Rob- lots of possibilities here. The parasites may be coming from many different possible sources- live foods, improperly quarantined specimens, live rock, etc. I assume that you are using bottled spring water? Regardless of whether or not it's bottled, spring water is really variable in both quality and chemical composition. Unlike distilled or R/O water, which has  specific characteristics, such as alkalinity, pH, nitrate, etc., spring water is a very vague label. It sounds like the algae problems are due to phosphate, nitrate, or silicate present in the water. I'd highly recommend utilizing R/O water. The money that you spend on a quality R/O unit will really pay for itself over time in terms of improved water quality, diminishing nuisance algae, and better conditions overall. Do some basic water tests on the spring water, and you'll start to get a handle on things, and what steps need to be taken to improve water quality. Good luck!>

RO Water
Hi,
I want to use a better water source for my saltwater/reef aquariums. I'm wondering about those vending machines outside grocery stores that dispense water. Would that water be safe enough for reef tanks? Also, should I add a dechlorinator to this water? Does RO filtration remove chlorine and chloramines? Thank You, Tim
<Safe for use, yes. No dechlorination needed... but I encourage you to look into getting, using either a reverse osmosis unit or R.O./D.I. for home use instead... much cheaper and cumbersome in the not-so long haul. Please see here: http://www.wetwebmedia.com/water4maruse.htm and the FAQs beyond.
Bob Fenner>

Ro/di for reef ..FO and discus.
Hello to all ,
Happy new year. Ant if that is you Cheers and thanks for the updates, for bocp1.
In setting up my fish room, I have been able to obtain a water quality report. while I can figure most out I thought you could help decipher some parameters.
Silica @ 4.8mg/l
O-phosphate@ 1.08mg/l
<This ortho-phosphate level is high for source water>
Total hardness and alkalinity are both followed by (CAC03)???
<Calcium carbonate... the largest contributor/component of water hardness>
with total reading60.6mg/l and alk @19 mg/l( Why are they both CAC03? Only inorganics (Chemical) found were copper at 0.01mg/l and barium? at the same 0.01 mg/l.
<Not a problem with regular, small water changes>
Of course no one will tell me ( vendors that is that I do not need some sort of tap water help)
<I would use at least a reverse osmosis device here... for your drinking and cooking as well as starter water for pet-fishing>
I am not wet behind the ears on aquarium keeping, I am just trying to get at least some straight answers.
Total solids at 119mg/l
fixed solids @67 mg/l
ZINC????? @0.4 mg/l
Free cl2(CHLORINE??) @.51 mg/l
<All fine>
The intended setups are FO Marine Reef  ( soft prop tanks ), Mixed display and (stony prop tanks) Africans, ( RIGHT FROM THE TAP I ASSUME) Discus Amazon sort of biotope ( tetras barbs... the gamut) in an old Odell 150g
<Wow, my arms, legs and back are starting to twitch! I've spent some memorable moments moving these fine folks big heavy glass tanks>
I saw on the pages that Bob was of the opinion if you drink it , use it in the tank.
<For the most part, yes... but I don't have as much phosphate in my tapwater... and still use R.O.>
I have decided that if I need a system, I will ro or ro/di in that wastewater can be for Africans and I just don, like having Muriatic acid in the house to recharge Kati Ani type units since there is a newborn in the house.
<Yes to leaving, storing this 3 molar hydrochloric acid in the garage, up high... in a locked cabinet. There are water filtration devices that don't use such dangerous rechargers though... like the Kold-Steril unit by the same folks that make PolyFilter>
However, I am just not sure that I really need a system at all.  What exactly is TDS and TDS meter ( I know total dissolved solids, but like what?)
<Total Dissolved Solids... you can look up on the Internet. Yours aren't too high (ours are treble what you list) for your applications>
Hey thanks again guys I hope I can make a decision fast as aquatic reef systems in Fla. is still pushing a 75gpd ro/di at an unbeatable price.
<Look at the large "hardware stores" offerings... this is what I use>
Though how about stuffing a pvc tube with a poly filter and carbon?
<Worth experimenting with. Bob Fenner, who would just get, use a reverse osmosis unit for now, use the tap on the Africans.>

Re: Ro/di for reef ..FO and discus.
hey bob, I just got your response and thank you very very much. You did say that you would look into a system for drinking and cooking as well. Is this due to the phosphate?
<Yes>
I know that you are not a medical Dr. but is there a reason for alarm that you might know of either for we adults and my newborn son.... Please reply I am somewhat alarmed, even though It has be safe by EPA standards. I do boil all water for infant formula. You also mentioned "starting with system with RO" I assume might as well for water changes too huh. Hey thanks so much for everything. It really is appreciated.
Kind Regards ,
Peter Eiselman
<Not a problem per se for human ingestion (in fact orthophosphate is better to have/use to rid source water of other metals)... but for pet-fish use I would start with water of low to no detectable phosphate period... and use the same water for your consumer uses (drinking, cooking). Tastes better. Bob Fenner>

Re: Ro/di for reef ..FO and discus.
Bob Thank you so very much . I think I will go to Home Depot after work and look. As far as you know ,I guess I could just keep th unit in my fish room and fill empty containers to put in fridge for cooking or whatever and drinking.... Though I prefer BEER! Oh yeah It is a no no to drink DI water though right? And you do not feel I need it given my h20 report.
<You can drink all. I prefer the R.O. during the day, beer at night. Bob Fenner>