They're beautiful fish who appreciate a rich herbivore diet. Being in the surgeonfish family, they lack the mucous lining on their bodies to protect them from certain parasites, especially the dread "Ich (aka Ick)". If you have a Fish Only aquarium (no invertebrates, keep some copper cure around. I've had 3 in my life and all 3 died of "Ich". It's the only species I've ever had to endure that fate. They are beautiful though. Oh, they also lose their color as they get older, and they can get big (too big for a 70 gallon), but if it lives that long in your tank, consider yourself blessed!