I have an idol, just got him 4 weeks ago though and hes still in QT.... I will agree with everyone that they are VERY PICKY eaters, but mine is eating seaweed sheets & silversides, I also put one of my coraline rocks in there ... he's doing fine and eats fine, you just have to figure out what he'll eat. On a side note, I've been thinking, if their main diet consists of sponges, why don't people just purchase sponges and put them in their tanks so the idols have something to graze on? Just a thought, haven't done it.