My rhom is about 6 inches now. I spend alot of time looking at him and watching him. I have never seen him poop. Ive never seen him trailing any poop. When I vac the gravel I see no chunks of poop going up the tube. When I look at him I cant even see where it would come out. When my oscars were this size there poop was as round as a pencil. Is this odd or what?