Before you convict him, I have a Hammers Cobalt Blue Lobster and thought he was eating my fish(in 55 gal). But what was actually happening was the fish would get stuck to the intake on the powerhead(has screen, but if the fish swam just in right spot they got stuck) and the lobster would come along and pluck the dead fish off. I came home and found the fish stuck before the lobster found did.
Once I put filter attachments on powerheads, no more fish deaths.
My RTS shares a tree trunk with the lobster and sits across his claws from time to time...Lobster could care less.
Mine has definitely learned when feeding time is, I make sure I drop food his way and he totally ignores the fish and makes a b-line for the pellets/etc.
I see fish swim right through his claws all the time and he seems to have no interest at all in the fish...Dead ones however, he will chomp right up.
Mine likes the Nutrafin spirulina meal tablets, bottom feeder sinking food tablets(one with clown loaches on label) and shrimp pellets.
I usually drop some flakes in to get fish feeding and he comes out to look for dropping food. For a while I would practically place the pellet in front of him each time I put flakes in. He seems to have learned...