whatever you decide, you will need to keep your Cray on its own till it matures, though community's have been known to work, as stated above, it is a big risk. i would not consider doing any thing till you have done some research on the Cray and the type of fish you keep. whatever you will need a mature and peaceful community, before you even consider it. If you decide to go ahead, i will help all i can, but you must be aware, that it may still end in disaster.