A while back I bought my daughter her very first fish. She got a yellow betta, and a pink 1 gallon betta tank. After having trouble keeping the amonia down I decieded to up grade her tank and bought her a 2.5 gallon tank.

So now I have this one gallon tank. I thought about maybe using it to grow water plants in. But my problem is,,,, I don't have any more free outlets. So I was wondering if I could get my plants to grow in a tank with no filtration? Will they grow in regular non fish water, or do I need to put the fish water from a water change in the tank?

If you still decide to go through with it, I'd recommend using old fish tank water. Plants need a source of nitrogen to help grow, so fish tank water is the best source. I don't think you'll have to depend on much filtration, but generally I like having some sort of aerator so that the water doesn't become stagnant.

Leave the tank by a window or near a direct sunlight