I have a few plants in my tank an Amazon sword and a couple of wisteria (I think). any my sword just doesn't seem to be growing. I'm remembering someone once saying there is a tablet or something to put under the gravel near the plant to feed it. Does that sound right to you guys and do ya'll know what its called. Also any other advise would help. just plain aquarium rock's and the light that came with hood I haven't even attempted the WPG calculation yet.