I just bought a new tank and it came with about 80 pounds of live rock and one mushroom coral. I preveusly had a 20 gallon salt water but it was fish only. I have got the whole thing set up and everything is doing good except the Mushroom coral looks funny. It has white stuff comming off of the stem. other than that it looks okay but im not sure if it is dead and if i should take it out? please help