What are these zoos called?

I don't know what your zoas are called but when you got your Green Clown Goby did he hide a lot before coming out? Ours only comes out to eat. He takes a Mysis then swims away at light speed, then will come out when he is ready for more. The only shots I get of him are a blur. He never comes out during the day. He is such a cool looking fish.....I just wish he chill out in the open like yours.

whoa! heh, those ridge-looking corals are awesome!