just saw this in another thread! please dont put armatus and ray together!! just like fly river turtle one day s**t will hit the fan. i had several different armatus too but the last one 16" took out the entire eye of my black diamond. black diamond died 2 weeks later. i didnt know it was armatus until 3 weeks after first attack a deep gash right on the disk of another blackray. looks like someone sliced it with an exacto knife. to be honest my only assumtion was this armatus thought the big white spots on a black disk were pieces of shrimp as there was no other tank mates. my fish are fed at least daily so he wasnt a starving armatus. end of story got rid of armatus. just lookin out for other member always roll of the dice.