Corals and clams look great fish not so much, unless they are a wider profile fish. I have seen a few. Had 2 300g rubbermaids set up years ago 1 with typical nonreef safe fish and the other had 2 bamboo catsharks and a coral catshark. The sharks were cool, the puffer was cool hard to tell which angle was which depending on how close they were. No corals in these.