[Delphinus]

I thought I read somewhere that the energy that can be derived from zooxanthellae is more like quick-release sugars, whereas the energy derived from feeding can be more like slow-release proteins. So it's like a candy bar diet. Sure, you can subsist on it and have loads of energy, but it's hardly a healthy long-term diet thing.

Having said that, if you feed the tank anyhow, odds are good anemones will be catching something. Probably depends on the species though. I know my carpets eat anything and everything that I feed the fish, and they're surprisingly adept at catching any stray morsel the fish don't snap up right away. Whereas some other species that are probably less quick on the draw and probably should be target fed. I do feed my BTA's shrimp and mysis, but I find once per week or thereabouts tends to be plenty.