View Full Version : Question about surface agitation, oxygen, and CO2
From reading articles in Aquaria Central, I gather that agitating the water surface increases the disolved oxygen but decreases the disolved CO2. So surface agitation is good for fish because it gives them more oxygen, but bad for plants because it takes away. But if you have plants, they're providing oxygen, so you don't need the agitiation you might need in a plantless tank. Is this correct, more or less?
Slappy*McFish
11-29-2003, 11:04 PM
To a degree, yes it is. Plants only produce O2 when photosynthesizing. At night, they use oxygen just like the fish and bacteria...so if you have no surface movement at night(in a CO2 injected system especially) you can have low O2 levels. A little surface agitation is much better than none..for the plants as well as the fish. It also depends on the plant/fish ratio(Too many fish and not enough plants to supply all the needed oxygen) as well as plants in low-light set-ups or systems without CO2 addition. The plants just aren't as active in these conditions and don't produce as much oxygen as in the high-light/CO2 injected systems.
OK, thanks for the info. I just have a couple of java ferns in a low-light 30 gallon tank. So I'll keep the water agitated.