RyanR, you are correct. The plants in a 20 gallon (as long as there are several) would keep that tank basically free of nitrates. A beta will not put much nitrate in the water in the first place. You could keep a beta and never or at least rarely change the water. The problem you'll run into is there will not be enough of the chemicals and nutrients to keep the plants alive for long. Anacharis and duckweed might live for a while, but will need to be replaced, especially because you will be changing the water in there frequently.
Everybody on this thread should read "The ecology of the Planted Aquarium", by Diana Walstad. If you have ever taken a chemistry or biology class it will help to understand it, but it does have a lot of great information in it in layman's terms (I know, I'm a layman).
Everybody on this thread should read "The ecology of the Planted Aquarium", by Diana Walstad. If you have ever taken a chemistry or biology class it will help to understand it, but it does have a lot of great information in it in layman's terms (I know, I'm a layman).
