I bought a frag of some lunar zoas back in August. Ever since they have not done well in my tank. I have rastas, and a few other frags of zoas in the tank. These started out with fat heads and have since shrunk in size since. Coloring is still good but the polyps have shriveled. I have tried moving them around for different flow and different light intensity with no improvement. I dip all my corals in Coral rx when I first get them. I have tried revive, lugols, and a hydrogen peroxide dip nothing seems to help. Water params are sg 1.025, ammonia 0, nitrites 0, nitrates 5 ppm, phosphates are usually at 0 but sometimes gets to .003 ppm, Alk is 9, ph is 8.0 any thoughts? What placement in the tank have you had success with them?