water parameter question

[joestreich]

i am wondering what people are doing to get neutral water or even acidic water. i have a ro/di unit (just changed all the filters) and it seem that the ph is about 5.5 when it first comes out. if i let it stand for 24 housr the PH is up to 7.9. the gh and kh are still at 0 or very very close. i am wondering if anyone else had expierenced the same situation

Are there ideas of how i could lower the ph. i was thinking of adding an acid directly to the water. i could do this in barrells and get the water conditions i need then add it to the aquarium. not sure if this has been done before or if someone has please let me know ratios.

Any help on this would be appreciated.


joel

 

[tjudy]

What are you using to test the pH? pH meters are useless in RO water. Why... I am not entirely sure, but I have experienced the same readings you have when testing pure RO. Once it has been reconstituted the pH stabilizes.

For West Africans I reconstitute up to 25 ppm with RO Right from Kent Marine. If the pH is below 7.0 I use pH Stable by Kent Marine to increase the KH up to 1-2. Then I adjust the pH, if needed, with the Kent Marine pH adjusters (I use the non-phosphate pH reducer). When I am done the TDS is still under 100 ppm.

 

[electric eel]

i had exactly the same problems you are having.i was able to get the ph down with PH DOWN(not sure who makes it) but it was getting expensive.i have started using sodium bisulfate(200grams disolved in 1gallon of distilled water) i run my ro/di unit into a 55gallon tank.when its full i add enough RO RIGHT by kent marine to get my desired tds(you need a tds meter)i add 2 capfuls DISCUS TRACE by kent marine then i start adding my stock solution of sodium bisulfate(you can buy it at pool supply stores) 4cl at a time until i reach my desired ph.i've been able to maintain stable tds and ph from 4.6ph and 40ppm hardness(for dicrosus sp.) to 6.3ph and 80 ppm(and values inbetween also) i think with my water 4cl lowered the ph by .2 or so.i try to let the water age for a day or two before i use it to make sure the water chemistry is stabilized.i usually have some water left in my 55 gallon tank now when i start to refill so i just add as much ro right and sodium bisulfate(do not add the dry powder directly to an aquarium) as i need.if i remember correctly it took 40centiliters of my stock solution to get my ph down to 5.6 and keep it there when i did the first fresh 55gallon tank full.you are probably going to get loads of feedback on this but here is one option.hope it helps a little.

 

[joestreich]

well, i am glad to see that i am not alone here..... i was getting rather frustrated. thanks for the information and suggestions.

i was thinking about using a 32 gal tub i have, filling it with ro water, reconstituting it with ro right and then using hydrocloric acid to adjust the PH. Does anyone see a problem with this? i know this might not be the "safest" way but if done properly, does anyone see a potential problem for the fish?

 

[tjudy]

Get out your measuring cups and test kits and play with tap:ro ratios until you get a solution that has a KH of about 2. A KH that low will be more stable but still allow th epH to be dropped with weaker acid sources than HCl (not my first choice). There must be an issue with HCl, or it would be in use as a commercial pH reducer... it is a very cheap acid. If you want to try a generic acid source I think I would look at acetic acid (white vinegar). Keep track of the volumes you use so you can scale it up to your storage vat.

 

[electric eel]

i know an older fellow in my local club used muriatic acid(dilute hydrochloric acid) to adjust the ph of the water for his discus.PH DOWN is nothing more than dilute sulfuric acid.i personally can't see why it would matter if the acid is humic,tannic(or some other more natural means of lowering ph) or a chemically derived acid.the only reason i tried the sodium bisulfate is that i read on apistodave's website that he used it.i think it breaks down in water to make some type of acid.you may very well have answered your own question Ted.hydrochloric acid is cheap and readily available.i think sometimes the people that sell products for aquariums(and other things as well) want us to think things are more complicated then they really are and that therefore the solutions have to be costly.

 

[joestreich]

thanks Ted, i went a took readings from the tank i am setting up. it is a 90 gal and i am setting it for Geophagus OH Tapajos or..... i mean Westies( i had to say it since i am in that forum)

Anyway, the reading are as follows Ph 7.7, Kh 2, Gh 1.5, TDS 35. i think i have the parameters you were refering to. i should just be able to add some sort of acid at this point. i must admit that i have not used acid before (again i must say this in case big brother is watching) so if anyone has added acid to there water to lower PH, i would be interested in what type and the results you had. Ted this may sound dumb but does using white vinegar add an odor.

Thanks electric eel for your replies, i thought of using muriatic acid as well. Does dropping the PH .7 - .9 seem reasonable and attainable?

one other thought is i am using red flint sand as a substrate. is that sand inert?

 

[tjudy]

Red flint will buffer the pH up a little bit, but it should not take it up to 7.7 from 7.0. Your KH is in the range you need it to be in order to safely lower the pH without crashing it. However, if you are going to add a chemical other than something formulated for an aquarium I would not do it directly in the 90 gallon tank. Pull 5 gallons from the tank, lower the pH in the bucket (maybe put some gravel in there too) and test it on some feeder guppies or something.

Anything else in the tank, like a carbonate rock (coral, limestone, dolomite...) that might be increasing the pH?

For what you are planning to keep I think your water parameters are fine. If you still want to drop the pH your GH/TDS is low enough that using pH Minus from Kent would not raise the GH/TDS very high. I think you would be fine with a TDS up to 250 ppm. Geophagus do nto really care.

Ted

 

[joestreich]

thanks Ted,

there is not anything else in there except driftwood.....which i could always use more of. Do have anything branchy?

That is a good idea to pull out some water and test it there, the only reason i was going to test it in the tank is because there are no fish in there right now.

i am also trying to figure out this water to achieve the right parameters for my westies. the problem is bigger than the one tank. Unfortunatly, i discovered this when i was setting up this tank. ideally i would like to come up with some formula and keep some in barrells. Before this i was jsut adding ro water and some tap and things just seemed to work out. Now that i have a TDS meter and PH meter I realized the error of my ways (ignorance is bliss i guess)

i am still not sold on PH minus ($$) when i get muriatic acid for cheap. i am just worried there might be other problems. has anyone used muriatic acid for lower their ph?

 

[tjudy]

I have a can of pH Minus that has lasted for about 2 years. I really do not use a lot of it. For my westies I do nto use ultrasoft water all the time. Only when I want to spawn them. Most of the time they are getting a mix of 50/50 RO and tap. They still spawn but I get bad sex ratios with the Pelvicachromis and Nanochromis. That is the only reason I drop the pH and hardness at all. I do not change a thing for the other westies (Chromidotilapia, Teleogramma, Hemichromis, etc...). My tap water is TDS 250 ppm, KH 14+ and pH 7.8. After cutting it 50/50 all those values are reduced to 100-125 ppm, kh 5-7 and pH 7.3 - 7.5.

 

[joestreich]

i will take measurements of my tap and of a 50/50 mix in a bucket with some gravel and in a bucket without some gravel. maybe this is the issue.

Ted, do you have any wood that is brachy for sale?

 

[tjudy]

Jeff is the wood source now. Click on the yellow 'wood' and it will take you to his site.

 

[electric eel]

hi jeff,the old guy in my club i was refering to was known as "discus ****" and he is retired now and not active in the hobby anymore from what i understand he was very successful at breeding discus(i phoned him last year and he told me that he had used the muriatic acid) sodium bisulfate is very cheap(i think i paid 5dollars for 2lbs) and it goes a long way(i've went thru quite a bit of water since i started using it and still have over 3/4ths of the first gallon of stock solution i made) i have'nt killed any rams or anything yet.my dicrosus filementosa spawned the next day first time i used it and my rams are spawning regularly(but for some reason i'm not having luck with the fry like i always did in the past.should have kept a journal i guess but i'm also not able to invest the time i did in the past) i was hoping apistodave would answer in when i posted similar problems to what you are having but he did not.maybe he would answer some of your questions if you pm'd him.i wish he would reveal his "method" to all of us.

 

[dw1305]

HCl

Hi all,
Been on holiday, but back now and both the family and the fish are fine.
I think the answer to the HCl (hydrochloric acid) question is that HCl is very "strong" acid, meaning that even a very dilute solution has the potential to acidify a large volume of water. R.O. is unbuffered (it's just H2O, really H+ & OH-), so even a drop of 0.01M HCl (which will dissociate completely into H+ and Cl- in a very large volume (say a 100 litres) will cause the pH to drop drastically (pH is a log10 scale of the ratio of H+:OH- ions).
cheers Darrel

 

[joestreich]

well i have been adjusting my ph with muriatic acid. i have got the the right mix of ro and tap to give me a ph of 8.2 and kh of 3. i then begin to add the acid (slowly and in small no tiny amounts). so far it has worked and no ill effects on the fish. My ph is now 7 and kh remained about the same, increeased a hair.

I would caution anyone attempting to do this. Muriatic acid is fairly strong and should not be taken lightly. Just a quick story, i was adding the acid with a plastic syringe and as i was adding the acid the syringe seemed to get stuck. i pushed a little harder and then it shot out fairly quick creating a splash. It could have easily gotten into my eyes. i found that sticking the tip of the syringe under water is a much safer way.

 

[Bilbo]

I have found the cheepest solution is swimming pool pH down, its sodium biphosphate and seems to work well.
I dont use any products anymore as my water supply is pretty close to ideal now but for a long time my water was pH 8.5 - 9 and almost 900uS from the tap and I had to peat filter for 2 weeks before I could use it

 

[electric eel]

thats what i use bilbo.i must have gotten the chemical name wrong.it works really well and the ph stays pretty stable(its really cheap to use also as you said) IT IS BISULFATE

 

[Mike Wise]

I cannot recommend mixing HCl in an aquarium containing fish. A small mistake can crash the pH and kill fish. It is much safer to use it in a mixing tub. When the water is at the proper pH, then add it to the aquarium. I've used HCl in the past. Very little will drop the pH of 2º dKH water very quickly! I used Muriatic Acid - an industrial grade of HCl. It is just as effective and much less expensive.

 

[joestreich]

just to be clear, i am mixing in a seperate tub and then adding to the aquarium. Also i am using muriatic acid.