Bitten (and squirted upon many times) by a particularly ornery but beautiful clown trigger I maintained several years ago. No damage. More recently, bitten a few times by my male Crosshatch. This usually happens when I'm feeding and move the hand holding the cup a little too low. Once, however, he literally cleared the water and nipped my hand causing me to jerk the cup back and shower everything around me in Mysis, Formula Two, Prime Reef, siversides, and saltwater. He, in the meantime, actually bounced off my tank brace and back into the tank. No harm done, if you don't count his not getting breakfast that morning and my finding out I could scream like a cheerleader.