Not all corals will do well in a nano-reef. So if setting up a small reef tank, research your corals well. To be a successful nano-reefkeeper, realize that some corals will grow too large, and some will require constant pruning. Some corals produce slime and metabolites that can be harmful to themselves or others if not carried away by a strong water current. And because space is limited in a nano-reef, you must choose corals that will not outgrow a small aquarium, and these corals must be able to survive in such a small environment. Nano-reefs differ greatly from normal-sized tanks in that you may not be able to provide adequate lighting, trace elements or water movement.
Good nano-reef coral characteristics are easily pruned or fragged, not aggressive and are slow-growers.
Some good corals for nano-reefs include:
Large Polyp Stony corals
Acans (Acanthastrea spp.)
Pineapple corals (Blastomussa spp.)
Euphyllia species, such as E. ancora and E. paraancora
Tree corals (Sinularia, Lemnalia and Litophyton spp.)
Clavularia and Pachyclavularia species
Mushroom anemones, such as Discosoma
Ricordea species, such as R. floridea