i had one for almost 2 years.it was 1.5 inches when i got it.and almost 5 now. it is one of my favs. but it reacently got an attitude. i did everything i could but i had to get rid of it. there great fish vey hardy,but like people each fish is different in personality.i keeped it a 90 gal. fwlr with a niger trigger,bird wrasse,figi devil damsel,3 puffers(2 dogface/porcupine),and 1 midas blennie.that little blennie is probly the toughest fish in my tank now that my humu is gone. please don't take my humu as an example for all of them all.i know people who have had no problems with them.