i have a 24 gallon nano cube which is pretty similar and i have done well with all soft corals (ex gsp, kenyan trees, xenias, zoos, etc) I have some lps in there too like frogspawn and torch and they have done well, but you have to keep them in the upper part of your tank to get enough lighting. Ive tried sps and it did ok, but never well, Hope that helped.