I have a trumpet or candy cane coral with about 20 separate heads on it. It has been in my tank for a few weeks, but has not yet bubbled out. All of the heads are fluorescent green, but won't come out. Any suggestions as to what they might need? It is toward the top of the tank. It is a 150 gallon 48" x 30" tank with T5 lighting. Everything else does great. Thanks.