My 6G hope to be reef

[T-2-T]

I had a 5 gallon with 1 clownfish, 2 turbo snails and 1 skunk cleaner shrimp and about 7 onds of LR with 1 mushroom soft coral and am wanting to make it a real reef.....any ideas of corals or smal anemoes to add?? its a super clean tank because of the availability of maintanence...please help me out