I am picking up a adult clown knife from the pet store mainly because I feel bad seeing it in a 20 gallon tank up there. I will be putting it in my 135 gallon tank with a 10" pleco. I also have some juvenile oscars that I will be raising in a 40 gallon tank so my question is when my oscars get big enough (5" o so) can I put them in the tank with the clown knife? The clown has been on a live goldfish diet