Thanks Bill, gonna shop for K2SO4.
For the plants to grow and eventually act as biological filter, what kind of water movement would be preferred? I would think that for the plants to grow, they prefer a slow water movement? I am thinking of using a landscape low pressure drip manifold and have it fed by a powerhead. I think each of those outlet can throw like 30gph, and i think if I use 2 lines per plant, that is 60gph per plant or a total of 240gph per manifold.