At 9" he's still a juvie so he can be moody like any other adolescent.
First things first though, temps, lighting, tank size, diet......
we need the run down to make sure everything else is OK before we can get into behavioral...
read "don't shoot the dog" it will give you an in depth description on how to train ANYTHING. using the methods described in that book, I was able to train a shrimp to jump into a net on command...