It's such a nice animal!(been wanting rays for a decade!(had a saltwater setup for bluering rays))... It swims, crawls, digs, a lot more than I expected, and eats a lot! I think they are kept in way to small tanks most of the time, it's a bottom-dweller, but a LOT of the time it's actually swimming(open water top of the tank(removed some of the wood to give it more swimming space) and crawling through the branches. I'm looking for a girl for him. Gonna build a 4x4x7.5 foot plywood tank similar setup just bigger, would it be possible to keep more than one pair? (I have heard different opinions about groups of rays, and most of what I have read was with respect to Leopoldi rays).