Lowering pH and adding CO2 - Aquarium Advice

Crow · 10-11-2003, 11:45 AM

I want to lower my pH and start CO2 fertilizing in my main tank. I understand that there are two ways that you can kill two birds with one stone here: Peat Moss or CO2. I've found plenty of info on how peat moss can lower PH but that only mentions CO2 as a side effect, and vice/versa on the CO2 fertilization.

Does anyone have experience with this, or can point me in the right direction to get more holistic info? I'm especially interested in the peat moss as I was thinking about using that as a substrate in a hoped-for Malaysian biotope tank. I haven't decided whether to go blackwater or not yet and want to learn more about it before I go diving into the shallow end of the pool. . .

shawmutt · 10-11-2003, 02:20 PM

Black water is actually tea-colored from the result of tannins from driftwood or peat, so if you have peat as a substrate you have a black water tank. I don't know anything about using peat as substrate, but I wrote a whole section on my black water tank here. You can see a picture of my black water setup in my gallery.

10-11-2003, 04:36 PM

I suppose it really depends on wht your starting ph is. I have one tank set up with peat moss as part of the substrate, and diy co2 on the tank also. However, I'm not using that much co2 on it, just one 2 liter bottle, so the co2 doesnt drop the ph much. Also, the peat moss is in the lowest level of the substrate, so it doesn't leave the water stained, or drop the ph too much either. With both of these in one tank, I still have a ph around 6.7-6.8. My tap water is normally 7.5 or so.

Crow · 10-12-2003, 09:07 PM

I have a 20gal right now. I'm planning on getting a 75gal somewhere down the road and setting up the biotope. Either Malaysian clearwater or blackwater. Malaysian blackwater pools and streams tend to pretty thick with vegetation, I guess they're not as acidic as S. American.

In the meantime, I'm using the 20 gal to experiment. My pH is around 7.6 and I want to get it down to 6.7-6.8. I also want to start CO2 fertilization for my growing # of plants.

But I don't want it to crash by going overboard, as both peat and CO2 fertilization both lower ph and add CO2. What I guess would really help me would be a way of measuring O2 and CO2 in the water. That way I could baby step my way in. Is there a way to do that which I haven't seen? Or am I just being overly paranoid?

The peat granules in the filter didn't do anything for you shawmutt? I was planning on trying real peat in the filter. . .

BTW, both of your tanks look great!