Unusual CO2 question.

[CajunCC]

In preparation for a 55 gallon planted tank, i've been messing around with a DIY CO2 generator. Since my water comes out of the tap with a pretty high KH (about 9-10 degrees) i didn't figure I'd see much of a pH fluctuation. But after running it on my 10-gallon test tank, i see it dropped the pH from around 8.5 to about 7. This is making me wonder what the effects would be of running CO2 on a non-planted tank as a way of lowering the water pH.

My only thought was that it would promote serious algae growth, but I'm willing to scrape more if the lower pH will make my discus happy.

 

[Bmeasure]

Yes, it works great for lowering pH. The only issue in using DIY CO2 to lower pH for sensitive fish is that it ISN'T stable (DIY CO2, that is). Over a period of about 3 weeks it will dwindle to all but useless amounts of production. Even using 2 bottles and alternating doesn't offer much satisfaction. Fork up some money for Pressurized CO2 and you can fine-tune your pH the way you want. It will be quite stable and last maybe 5 or 6 months in a 55 gallon. The more practical way is probably to use a reverse-osmosis unit to get pure water then mix with tap until desired pH is reached. You decide....but DIY CO2 will most likely let you down.

 

[slipknottin]

I agree, I would not rely on DIY C02 to give me a constant lower stable Ph, especially when you have a high Kh.

But a pressurized C02 system (possibly with a Ph controller) will give you an incredibly stable Ph.