i seriously beg to differ. i've seen it happen personally diving in a 5k tank.
could be size issues, ours were 3-4ft on 1ft circular dia. rays. they and possibly 2 puffers killed all 12 rays. we saw the bamboos eating the surely alive ray's edges, but suspected the puffers took the eyes of both sharks and rays. not that shark need their eyes at all, but the rays do.
this all happened fairly quickly in a couple/few months. i saw just about every day of it. unfortunately, i don't know anything about fish, i just worked there. so all the rays died. go rfcafe!!! go trexcafe!!!
:notsure: