sodium bisulfate

[electric eel]

i've been using sulphuric acid to lower the ph of my ro/di water.i bought a plastic container of sodium bisulfate and am going to mix up a stock solution of ro water and the s.bisulfate.does anyone have any idea how much i would want to add to a gal or liter of water.also any idea as to how much to add of the stock solution to a 55gal tank(ph 8.2 and hardness 16ppm)to bring it down to 5ph.i add just enough ro right to bring the hardness up to 40 to 50 ppm also.

 

[PsYcHoTiC_MaDmAn]

I'm interested in this, looks like an effective way to lower pH (given the natural pH of it is 1.4)

its much easier working out how to make the water harder, I dont know how you can calculate the effect on pH by a substance. and it wasn't something I calculated when I worked out my rift lakes mix.

 

[electric eel]

apisto dave talks about using it on his web page but no specifics.i just thought some of the forum members might have a "recipe" to save a little time.i will do trial and error if i don't get any input.i like to experiment anyway.i figure if i mix the stock solution the same every time then i would have a good idea as to how much to add to reach my target ph.i'll do it fairly slowly so i can figure out how much to add to lower my water a set amount.depending on which fish i'm doing the water for i may want anywhere from 4.5 to the low 6's.i generally mix my water in a 55 gal tank and let it rest until the next day to use.

 

[chris1932]

Sodium Bisulfate and Sodium Thiosulfate will lower pH, however they are an oxygen scavanger by nature and need time to go through an evolution process in that over time only the sulfuric acid byproduct is left behind. Use extreme caution and DO NOT add to water in an enclosed area. If start "tasting" an odd smell get some fresh air ASAP. The best thing to do is make a stock solution by weight 1 gram to 1 liter of fresh warm water, let all of the powder dissolve. Take a 1 liter container of water you are going to add to a tank and titrate that sample of water down to the desired pH. Calculate the total drops and multiply by total liters. NEVER add powder to the tank.

 

[oldschool]

Why not just use peat moss or oak leaves? I hate to fuss with chemicals. I have a barrel of water I keep for breeding my black water species, in that barrel I have a ton of oak leaves and I just let the water steep. I get water with a pH around 4.5- 5.5 and that seems to work for most any of my black water species. Just thought I would give you another option. Good luck with solving your pH question.

 

[electric eel]

i had 3inches of oak and beech leaves in a 20 long(barebottom) and the water got extremely dark.the ph never went below 6 without my adding something.i'm trying to figure out a reliable(and relatively) inexpensive method to get the ph down in the 4.5 to 5 range and keep it stable.i ended up mixing 200 grams of sodium bisulfate to 1 gallon of distilled water.my ph meter was acting up last night so i had to calibrate it.i got impatient so i didn't do this too scientifically(i don't have the proper stuff to do it correctly anyway).i put 10 mililiters of the stock solution in the 55 gallon tank and it lowered the ph .3.as i said meter was acting crazy but i went out 3 hrs later and added 40 mililiters more.i was shooting for 5.8(this is what i keep my discus at) and this morning the ph was 5.3.i'm going to wait until later in the day to use it and am going to check it again before i do.thanks for the input chris i will be careful(the makeup tank is strongly aerrated and heated-should speed up any chemical reactions).one of the owners of a lfs that i sell fish to told me not to add the powder directly to the water and said he had always had to use a lot to get the ph down and keep it down(i think he was using a mix of ro and tap water though)

 

[oldschool]

What is the KH of your water? Sounds like that is your problem, you need to lower your Kh in order to lower your pH. My KH is 0 and I get my pH into the 4.5 -5.5 range easily. What kind of water are you using? RO, spring, tap etc? If you are using RO water you may be adding too many additives and that is buffering your water. Peat moss or oak leaves will lower your pH safely using all those chemicals way too much work for me. Mother Nature has it all worked out. I have a well and I get water with a pH of 5.5 and 40 us/cm my KH is zero and I never have trouble lowering my pH. When I used RO water, for working with black water species, I never added anything to the water but peat moss or oak leaves. Hope that is of help good luck.

 

[electric eel]

i wish i had your water.mine is 8.2ph and in the 800s ppm kh.i've got an ro/di but either the water is tracking thru the di cartridge or i need a new one cause its coming out about 16ppm kh and should be close to zero(the lowest it has ever come out is 6ppm with a brand new cartridge).i do add ro right,discus trace and a small amount of set ph buffer(either 5 or 5.8ph) to the water(i want the water to have some buffering capacity)i don't have a problem using chemicals.apisto dave says on his website that he uses leaves to bring the ph down to 6.3(i think) and the sodium bisulfate to take it on down.i just assumed leaves wouldn't take the ph any lower and as i said it didn't in my tank with dicrosus and i didn't add anything to their water but just enough ro right to bring the kh up to 40ppm and also some discus trace(which isn't supposed to affect hardness at all)i think i've figured it out though the water is still dead on 5.3(that i just made up last night) and thats the main thing i'm looking for is stability.there are only a handful of people in our club(and we have a big club.usually 50 to 75 at meetings) that do softwater fish and most of them are happy if they get their 6fry for bap points(they don't care if they are all female or what) i won't be happy unless i figure out how to get mixed sex spawns so using hard water and peat etc(which is what most of them are doing)isn't going to work for me.it sounds hard but if i do the same thing every time(i tried several different methods so far) the results SHOULD be predictable.i sure wish i had your water though. i used rainwater for a while but things were very dry here last summer and fall.

 

[dw1305]

Sodium bisulphate

Hi all,
Sorry I've only just caught up with this thread.
Electric Eel, I'm sure there is something wrong with your de-ionizer, our water is very hard, about conductivity 800MicroS, and all most infinitely buffered, but is down to 30microS when it's been through the de-ionizer (even when the resin needs re-charging). Distilled water is about 6 micro-S, at those sorts of levels an addition of a small amount of relatively dilute weak acid, like humic or carbonic acid, can cause a catastrophic drop in pH.

As Chris says your water must still be buffered (The KH reading) or the pH will just drop unpredictably when any acid is added. Any sodium bisulphate solution (in pure H2O) will drop to pH 1.4. Your pH buffer works by being a compound where it is insoluble but which becomes soluble at the appropriate pH, along as you have an excess it will buffer your water, but as soon as it is all neutralised (there is no insoluble buffer left), your water will be unbuffered and the pH will rise or fall dependent upon which ions (+ or _) are in excess.

Have a look at Wikipedia:
<http://en.wikipedia.org/wiki/Sodium_bisulfate> this would suggest that it might be worth looking at the suggested dosage per gallon for swimming pools.

Personally I wouldn't do anything until you've got a pH meter you can rely on, there is the possibility the pH will drop low enough to kill your fish, any excess of sodium bisulphate will utilise all the available carbonate hardness before it's neutralised and then your pH can potentially fall all the way to pH 1.4.

I think even if you can get your pH down the amount of solutes in your water (particulalry Na+) will stop your fish breeding, although other people will probably disagree.

cheers Darrel

 

[electric eel]

you've got me scared now darrel.my meters working fine now but maybe i will wait until tommorow to use the water surely it would be stabilized in 2 days.i will check kh,442 and nacl with my tds meter also.maybe i will go back to using acid.i've been using a product that i bought at an aquarium store and was looking for a cheaper option.could try dilute hydrochloric(this is what one of the discus guys uses here) i guess.i'm going to give this a go i think first.i talked to a guy from siemans water technologies(they do industrial water treatment) i was going to buy an industrial di cartridge(holds about 20 kilo's darrel) but he said my water pressure was way to low and that my water would track thru the cartridge.i'm having to run cold water thru my ro so i know its not working very efficiently.this whole undertaking(the softwater fish) wasn't very practical for me but i wanted to give it a shot.i used rainwater on my ram breeding pairs(hardwater on the fry) before but that isn't a reliable scource of water around here.

 

[dw1305]

Hydrochloric acid

Hi Electric Eel,
Low water pressure would definitely be a problem, as you need sufficient pressure to force the water through the resin.
Hydrochloric acid would possibly be a better option, but you have the same problem that it doesn't have any buffering, it instantly disassociates into H+ and Cl- ions. It's a strong acid so I'd make up a very weak solution of acid, by dripping it into a 10gallon container a drip at a time, giving a good stir and waiting until the pH stabilises. You shouldn't have to wait long as the acid is all in solution instantly.

I don't know about the fish safeness of weaker acids, humic (from peat) and carbonic (from CO2) are definitely all right but I'm not sure about citric acid or sodium citrate, (this is the buffer we use in the algal cultures at work).
Phosphoric acid is used, but might not be a good idea in tanks with lots of light.

Our geology here is the same as yours all limestone, and I gave up on the idea of trying to keep blackwater fish, as even our rainwater has some carbonates in it (pH 7 -7.4, 180MicroS), A. cacatuoides, A.trifasciata and A. borellii have all bred in it, and A. "Blue-steel" were happy in it, although they didn't breed, (see the "Blue-steel and Camallanus" thread).

Cheers Darrel

 

[electric eel]

hi darrel,initially i was trying to mix ro/di and tap using seachem products to lower the ph.it was taking so much product to get the ph down


i just couldn't afford it.i was suprised when i got the tds meter how much was in my rainwater also but i had great luck with rams(thats what emboldened me to go a step further)there are only a couple people around here that breed rams at all.its hard to find local tank bred ones.i was making money on them but it took all the fun out of the hobby for me.the sodium bisulfate seems to have worked fine.the ph was still a stable 5.3 kh ended up around 100 ppm and nacl was 66 which is less then a tenth of my tap(710ppm) i'll figure out how to get the values i want.the industrial di cartridge takes a crazyhigh water pressure but my water pressure is on the highside of borderline for an aquarium unit.the inline water pressure booster cost about 100bucks more than the whole 50gallon per day ro/di(its crazy)money's tight right now so i'll have to make do for now.i'm having fun anyway!

thanks for your help
craig oliver

 

[dw1305]

Hi Craig,
Rams aren't easy to breed so that is an achievement. Hope you get on all right, with a de-ioniser. I did consider an R.O. unit, but our tap water is very hard so we would have had a large volume of "waste" water for each litre of R.O. and restricted membrane life.
cheers Darrel