I you want DO NOT have a moorish idol, if you even can get one. I volunteer at a zoo in Wa state and they had one for about a year, and it eventually died. Try the bannerfish. I see they are also called the poor mans moorish idol.
I worked in aquatics for PETCO before the movie came out. I however, volunteer at a zoo in Wa state and when they opened the new sea horse exhibit, they had a clown fish. Oy, for how many times I heard "look its Nemo" that summer.