I have one clown and a rose bubble tip anenome in my 12 gallon AquaPod. He attacks my hand when I put it in there, I can't imagion what he would do if I put in another clown...they typically don't get along so well.
Buy some "Stability" (white bottle w/ blue writing) for your tank and add it with your live rock and sand it will help, but you still want to be patient...nemo will thank you for it
