Large Polyp Stony (LPS) Corals are a great choice for beginner-level hobbyists.  

Stony Corals of the Order Scleractinia are the architects of the reef structure. Scleratinia are characterized by having 6-fold symmetry as well as a calcium-based skeleton. 6-fold symmetry means the coral has six tentacles or tentacles in multiples of six. 

LPS Corals

Ausie Neon Green Hammer (Euphyllia Ancora) - 4 Heads