I first got the Derasa to clean up my green tank. It is really working, the tank is much less green (yeah yeah laugh at my Handle !) After he is finished with the natural phyto in the tank, can I spot feed him with a liquid or perhaps a powdered phytoplankton? Do they eat any Zooplankton or rotifers? Do i just add it to tank and hope he gets it? Eventually i may culture phyto, or get Bottles of DT's, but its a far drive for me to pick that up! Plus is a lot $, so if the dead stuff will do, I would prefer!