Originally Posted by goh
Hi Boon Yong,
If I read correctly, your tank is ~400L with only 108W, > 1 WPG.
This is really a low light tank. For low light tank, you usually don't have to worry abount CO2 level. Many low light tank don't even inject CO2.
Tom Barr's opinion that high CO2 level helps to elimiate BBA usually refers to high-tech tank. It should not be necessary to maintain high level of CO2 in a low light tank.
I am not sure whether it could be due to your dosing as you seems to be dosing quite a lot of NO3 for a low light tank with mostly crypts,anubia and moss. You did not mention the fish population and feeding pattern. Low tech tank may not even require dosing of nutrients if the fishes are well fed.
Yes, the lights are low. In fact, my Aponogeton ulvaceus has grown so big that it covers half of the water surface and shades most of the aquarium. So, there is indeed very little light going through.
So with little light to start off with, maybe I don't need so much CO2 since the rate of photosynthesis will slow down. But I still do not understand how to prevent BBA from spreading.
So in low light tanks, it's not really necessary to inject CO2 but that in turn encourages BBA growth since CO2 is inadequate? I don't quite understand it. How does the low-tech aquarium concept by Diana Walstad overcome this problem?
My fish load is fairly high, about 150 tetras in all. I feed them tetrabits on a daily basis, either once or twice, depending.