Hey there-
I've never kept an angel in the reef, but may people have good luck with
Centropyge argi, the pygmy angel. These little guys dont seem to bother much of anything. It's hit or miss with most of the rest...but most seem to behave. You won't know till you try. Heck, I put a un-reef-safe butterfly in my tank and don't regret it one bit. He's eaten a lot of critters (worms mostly..and aiptasia)..but he sure is pretty

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One comment on the caulerpa. And Tom, Horge, Chris...or anyone else correct me if I'm wrong....but wouldn't the caulerpa need a break from the light to photosynthesize "correctly". I know caulerpa will grow just fine with a light/dark cycle. Any chance that the constant light could have caused it to go sexual and just dissolve?
Anywhoo..have fun picking out a fish. The
bicolor angel is truly beautiful. It would be high on my list. This guy, the C. multicolor is very, very high on my list too.
http://www.themarinecenter.com/multicolor.htm
Brooke