im setting up a 7x2x2 and would like to get a couple of rays i've kept fish for years but quite fancy keeping rays now.Other fish that will inhabit the tank are a half grown giraffe catfish(this fish has been kept with rays before by the previous owner with no probs)and i'd like to get some peacock bass, siamese tiger fish and an arowana,so could someone tell me what type of ray would be best to keep in a tank this size and with the fish i have in mind. Or if you see any problems i might have by mixing these species of fish together please let me know,cheers gullywhippet