MOORISH IDOLS
moorish Idols can be easy to keep. You have to get a small one (2 1/2 to 3 inches). Need to feed it a lot and many times a day to 'bulk it up'. Small ones will eat anything, they are omnivores. If you watch them on a reef, all day long they pick and search for food. If you get a bigger one, they will pace back and forth all day long and may not eat. They will nip at clams and some corals, if you have a reef tank.
You should assume it has ICK as with any new fish and treat it, not just quarantine. The best I have done is 2 yrs and 3 yrs with MI before a 'tank crash'.
I have 2 small one's in a 10 gallon quarantine / treatment tank, (formalin bath and 3 weeks hyposalinity) lights are off unless I am home, then I feed every 15 minutes and do a 80% water change each night. They are still a little fussy on what they eat.
If you have any questions, let me know. Send you phone number if you want a call.