Yeah The green one is Hynopora Rigida. It does have a very potent sting, luckily the sweepers are only about a 1/2 inch or so long. Its a very easy to care for coral and will grow fairly fast for "hard" corals. The skin covering it is very thin and very delicate and easily damaged. It is very easy to prompagate by breaking off branches and glueing to rocks. Looks very bright green under heavy actinic lighting.