Hi, not sure if you are still looking for plant recommendations, but if you are, I would suggest you look into getting pearl weed and like another said water sprite. I have those two plants (along with several others with sand substrate) and they grow extremely fast. I started with only a few pieces of pearl weed and now I have enough to have in 2 tanks - a huge amount. And the 1 water sprite has turned into 6 (maybe more) plants.