Aloha, I'm just getting into Aquaponics and this is my first experiment.  I am running a 20 gallon fish tank (FT) and a 21.5 gallon grow bed (GB).  My auto siphon is set at the 20 gallon level in the grow bed leaving roughly 1 1/2 " of dry gravel on top.  The total GB depth is 15".  I started cycling the system three days ago using the Peemonia method.  Two days ago I added a hefty amount of bio…