How Do You Guys Control Ph With Co2 Infusion?

[Seed]

I've just started using a DIY CO2 generator in a community tank. My problem is that my tap water has zero buffering capacity.

I didn't think this was going to be a big deal until I went to several LFS's to find a buffer, and realized that every single buffer solution available to me is phosphate based, so a no-no for live plants.

So then I figured well, I'll just up the pH with sodium bicarbonate. The problem with this is that I am getting fluctuations in pH as the DIY kit produces less CO2 throughout the week. As it produces less CO2, the pH in the tank rises swiftly because of the bicarb. This is no good at all for the fish in this particular aquarium, having the pH swing from acidic to basic all over the place.

What I need is a good buffer that is safe to use in planted aquariums to take care of the problem. Wondering if anyone has any recommendations?

 

[Renate]

I am in the same situation as you are. I want to add diy co2 but Kh is normally 0. At times I get the Kh up to 3 using baking soda. It also raises the the ph., I put flourish excell in water which ph is 8.4. and ph goes to 6.4. Then added baking soda and ph is 7.2.

Someone advised me to start off slow and watch the ph. Don't have time to do that yet so haven't started diy co2.

 

[Seed]

For now, unless someone knows a phosphate free buffer solution (or otherwise plant friendly) that will keep pH around 7.0, I have added a valve on the CO2 line into the powerhead. I am hoping that I can reduce the amount of CO2 into the tank this way and keep pH more stable.

I'll let you know if this works at all. My fear is that doing this will make CO2 generation a complete waste of time as I can't infuse enough CO2 into the water to make a difference.

 

[Renate]

I would like to know how you made your co2 with the powerhead.

At this site http/www.####.co.uk/Diyco2.htm
Read that Cathy Hartland increase the buffering by adding some crushed coral (from the saltwater tank supplies at the lfs) in a filter bag in your filter. This will slowly dissolve, releasing calcium carbonate which will increase your KH. You will also see a rise in pH (the two parameters are chemically associated), but the CO2 will drop the pH back down again. You will have to use trial and error to determine the exact amount of crushed coral to use in the filter bag for your tank. Remember that after a large water change, the KH/pH can drop noticeably until the crushed coral dissolves into the new water.

Also read that using eggshells, or oyster shell, which is in bird grit, is usefull for raising the Kh.

At present I am experienting with baking soda and egg shells in my 29 gallon tank

 

[Seed]

The powerhead has in inlet for air intake. I bought some extra intake hose and some air line fittings. I used a "T" splitter on the powerhead's air intake hose, with one side of the split taking in regular atmosphere and the other taking in CO2 as it is produced from the CO2 generator.

I figured with this I wouldn't need to bother with a diffuser, and I am pretty sure I was right due to my pH hell problems.




EDIT
I've conidered using crushed coral etc. The problem is that I don't want the pH to swing high when the C02 levels are low, I was wanting a more neutral buffer. Crushed coral would keep the tank at 8.0 pH when CO2 levels are low and I don't want it nearly that high, both due to the fish in the tank and because I want the swings to be considerably less if I have to deal with them at all.

 

[Dave Spencer]

For now, unless someone knows a phosphate free buffer solution (or otherwise plant friendly)

Plants need phophates! How is the buffer unfriendly to plants?

Adjusting the kH will bring greater grief to your fish than the pH.

Most of us using CO2 experince pH fluctuations throughout the 24 hour period with no problems.

Dave.

 

[Seed]

Every single thing I've read about buffers, including the labels of several buffers, says that phosphate based buffers shouldn't be used in aquariums with live plants. I haven't bothered to dig deeply into what the reason for this is, figuring if they say don't do it, I won't. Especially considering the aquarium industry's tendency to downplay the negative effects of their products ("change your filter pad once a month," "feed your fish at least three times a day!" etc etc, you know what I mean).

If all of this is incorrect, then I would be more than happy to use a phosphate based buffer in the aquarium. It would certainly make things easier. I want to be more certain first, so any information you can point me to in that regard would be greatly appreciated, i.e. literature that explains why phosphate buffers are fine or what to be careful of.

The fluctuations I'm seeing are severe in my opinion and I do not want stress the fish with pH swinging from less than 6.0 to 8.0 within less than a 24 hour period. This is not even taking into consideration the necessary weekly partial water change, which compounds the problem, i.e. how do I formulate the water for water changes if the tank water is all over the place all the time?

The same with KH really. The goal is to set it up so that I don't have huge fluctuations with ANY of these parameters. I understand that I won't be able to eliminate swings entirely, but I sure would like them to be greatly lessened.

 

[Dave Spencer]

I suspect they don`t recommend using the buffer with plants because the plants will use up the phophates and neutralise the buffering.

I have very soft tap water at around 2dKH when I lasted tested it 1.5 years ago. I inject pressurised CO2 to around 30ppm with no pH issues or so called pH crashes. This hobby can be filled with scare mongering, most brought on by inadequate test kits IMO.

If your fish are happy, leave them that way and don`t mess around too much with the kH, as this will harm your fish more than the pH.

Using an air line alongside DIY CO2 will make injection a waste of time.

Dave.

 

[Seed]

I suspect they don`t recommend using the buffer with plants because the plants will use up the phophates and neutralise the buffering.

I have very soft tap water at around 2dKH when I lasted tested it 1.5 years ago. I inject pressurised CO2 to around 30ppm with no pH issues or so called pH crashes. This hobby can be filled with scare mongering, most brought on by inadequate test kits IMO.

If your fish are happy, leave them that way and don`t mess around too much with the kH, as this will harm your fish more than the pH.

Using an air line alongside DIY CO2 will make injection a waste of time.

Dave.

First, I should point out that I'm not a novice to fishkeeping, especially in dealing with GH, KH, and pH. My main tank is a mbuna tank, devoid of plants due to the fact that the cichlids shred them to pieces (I learned this the hard way early on lol). I've had that tank running for nearly 5 years. I am pretty experienced, both due to education and practice, in keeping all of those levels nearly constant, with zero buffering capacity water and without using crushed coral (there are reasons why but they are not really important to the discussion). In this other community tank I have the plants in, the difference is that I've never had an acidifying agent constantly introduced into the water.

Now that I think about it, the warning about the phosphates is probably exactly what you mentioned. It should have occured to me. It also gives me an idea that I will need to experiment with, thinking I may be able to use that attribute of the phosphate buffers to my advantage.

As far as my CO2 injection method, it appears to be working well enough despite your opinion that it won't work. There is no other explanation why I see such fluctuations in pH, when I do not nor have I ever seen such fluctuations in my other tank or my tap water. The only explanation is that an acidifying agent is being introduced, and by far the most likely culprit is the CO2 that I am introducing. And yes I've actually done tests on both my tap and mbuna tank water to see how much pH varies from day to day, and the answer is that the tap starts off slightly basic and then becomes neutral, and the mbuna tank does not vary at all, which isn't surprising to me in the least. At any rate, I don't see why mixing it with air would make the slightest bit of difference, considering the agitated surface of the water adds dissolves oxygen, the filter outlet agitates the water and dissolves oxygen, etc. It may reduce the amount of... how do I put this... space available for other gasses to disolve into the solution, but so does the CO2. But like I said, based on the evidence that I've seen this method appears to be working well enough.

But all this is a huge digression anyhow. My main question was and still is, how do people who use CO2 injection stabilize the pH so it isn't all over the place? You said basically that you don't attempt to stabilize it, which is fine, but I wish to stabilize it if possible, so I'll respectfully wait for some other input on the matter.

 

[lljdma06]

I've just started using a DIY CO2 generator in a community tank. My problem is that my tap water has zero buffering capacity.

I didn't think this was going to be a big deal until I went to several LFS's to find a buffer, and realized that every single buffer solution available to me is phosphate based, so a no-no for live plants.

So then I figured well, I'll just up the pH with sodium bicarbonate. The problem with this is that I am getting fluctuations in pH as the DIY kit produces less CO2 throughout the week. As it produces less CO2, the pH in the tank rises swiftly because of the bicarb. This is no good at all for the fish in this particular aquarium, having the pH swing from acidic to basic all over the place.

What I need is a good buffer that is safe to use in planted aquariums to take care of the problem. Wondering if anyone has any recommendations?

All I use in my CO2 canister is sodium bicarbonate when my buffering capacity is low. I didn't need it in IL, but of all things, I may need to reintroduce it in Miami, of all places, as they have possibly added a softener to the city's tap. I hate it when the city messes with the water. It's all about me, you know.

Have you tried alternating mixes so that your canisters do not produce less CO2? As one mix lessens, the other will be fresh mix, thus regulating the levels a bit better. I have done this in the past to good effect. My pH never had such large swings. I know pH works exponentially, but it would never swing by more than .2 or .4 during a daily cycle, and that seemed to suit the fish just fine.

 

[Dave Spencer]

As far as my CO2 injection method, it appears to be working well enough despite your opinion that it won't work.

The only explanation is that an acidifying agent is being introduced, and by far the most likely culprit is the CO2 that I am introducing.

You will be degassing a lot of CO2, making levels potentially lower than your plants requirements. Adding CO2 water produces Carbonic acid, which is lowering the pH of your water.

And yes I've actually done tests on both my tap and mbuna tank water to see how much pH varies from day to day, and the answer is that the tap starts off slightly basic and then becomes neutral...

Do you mean when it is just left to stand, ie. in a bucket? If so, this is because tap water is usually well carbonated, which degasses off to the atmosphere, moving it to more basic.

At any rate, I don't see why mixing it with air would make the slightest bit of difference, considering the agitated surface of the water adds dissolves oxygen, the filter outlet agitates the water and dissolves oxygen, etc. It may reduce the amount of... how do I put this... space available for other gasses to disolve into the solution, but so does the CO2. But like I said, based on the evidence that I've seen this method appears to be working well enough.

Surface agitation will remove CO2 from the water that you are putting in, so you are wasting gas.

But all this is a huge digression anyhow. My main question was and still is, how do people who use CO2 injection stabilize the pH so it isn't all over the place? You said basically that you don't attempt to stabilize it, which is fine, but I wish to stabilize it if possible, so I'll respectfully wait for some other input on the matter.

With all due respect, people add CO2 to grow plants, not stabilise pH.

Dave.

 

[Seed]

You will be degassing a lot of CO2, making levels potentially lower than your plants requirements. Adding CO2 water produces Carbonic acid, which is lowering the pH of your water.

Of course, but I want to balance the needs of the fish with the needs of the plants. The plants in this tank were doing ok before I decided to use CO2, they just grew slowly. In the first week of adding CO2 to this tank their growth rate has quickened significantly. So while the amount of gas dissolved in the water may not be in the money zone that you strive for, it's enough to have made a difference.

Do you mean when it is just left to stand, ie. in a bucket? If so, this is because tap water is usually well carbonated, which degasses off to the atmosphere, moving it to more basic.

Yes, that's what I mean. And mine started off slightly basic and then moved to neutral. But it's not worth debating because the entire point of me bringing it up was to point out that something was acidifying the water; it wasn't occuring by itself.

Surface agitation will remove CO2 from the water that you are putting in, so you are wasting gas.

The purpose of bringing that up was to point out that unless your water is perfectly still, you will be having plenty of gas exchange with the atmosphere and will be losing CO2 regardless.

But all this is a huge digression anyhow. My main question was and still is, how do people who use CO2 injection stabilize the pH so it isn't all over the place? You said basically that you don't attempt to stabilize it, which is fine, but I wish to stabilize it if possible, so I'll respectfully wait for some other input on the matter.

With all due respect, people add CO2 to grow plants, not stabilise pH.

Dave.

Oh my god lol. Where did I ever say I was adding CO2 to stabilize the pH? Never once did I say that's what I was trying to do. I want to know how people with no buffering capacity in their water stabilize their pH DESPITE the fact that they are adding CO2. Not using CO2 to stabilize pH, that's one of the more absurd things I've ever heard.

You said that you don't attempt to stabilize it DESPITE the CO2 addition, which again is perfectly fine, but I wouldn't mind hearing from people who do attempt to stabilize their pH (preferably people who are successful at it) so that I may use their methods, if indeed such people exist. You aren't that person, but thank you anyhow for your replies.

 

[Seed]

All I use in my CO2 canister is sodium bicarbonate when my buffering capacity is low. I didn't need it in IL, but of all things, I may need to reintroduce it in Miami, of all places, as they have possibly added a softener to the city's tap. I hate it when the city messes with the water. It's all about me, you know.

If they purify the water as much in Miami as they do in Sacramento, get ready for some pH fun. My water is <1dGH and <1dKH out of the tap. I probably couldn't have less buffering capacity unless I was using distilled water haha.

Have you tried alternating mixes so that your canisters do not produce less CO2? As one mix lessens, the other will be fresh mix, thus regulating the levels a bit better. I have done this in the past to good effect. My pH never had such large swings. I know pH works exponentially, but it would never swing by more than .2 or .4 during a daily cycle, and that seemed to suit the fish just fine.

I haven't messed with the mixture yet. What I've done, and I'm happy to say that it has worked, is added a valve on the intake line to reduce the amount of gas getting into the tank. In 12 hours my pH is back where should be, but of course I will be checking the pH and adjusting the valve accordingly to keep things where I want them.

That isn't an ideal solution though, I'd really rather put more gas in and have the water be able to deal with it more, so still looking for ideas on that one.


Oh, I just realized what you meant by alternating the mxitures. That is an interesting idea, i'll give it a try.