Bubble Coral Receeding

[minireef guy]

I've had a large green bubble for about 6 months that began to receed about 2 months ago. It's body used to extend all around to the bottom of the skeleton. Now I can see the ridges near the main part of its body. It hasn't seemed to worsen in the past month and extends fully everyday. It also accepts food regularly. I've moved it farther away from the lights on the advice of my lfs, but will it ever return to the way it was? My open brain, brain, and octo-bubble, etc. are all healthy.

 

[adrian]

Im not sure moving it away from the light is the best idea. What type of lights do you have. Have you changed your lights lately, or do they need changed? Hows your water quality? Is there anything irritating it,a critter, or a near by coral? Give us a run down of your system.

 

[minireef guy]

I have 2 55w PC's. The bulbs are only a few months old and I change them every 6-8 months. I've read that bub's only need moderate lighting. Could new bulbs have caused this? Anyway, I change water with about 3-4 gallons of distilled every two weeks and have a wet/dry about the size of the aquarium itself attached to a 300gph pump. Pump driven skimmer. No nearby corals at all and I've never noticed anything bugging it. I actually have no shrimp at this time and my fish leave it alone.

 

[adrian]

Water quality, (Ca, alk, pH, salinity, temp, ammonia, nitrite, nitrate)? If the corals in the tank were not properly acclimated to the new bulbs, the new intensity could shock corals and cause problems.

 

[minireef guy]

8.3, 1.025, 78 deg., ammonia, nitrate-trite negligable.

 

[adrian]

Hmmm, is there anything on the skeleton where the tissue is receding? Have you tested PO4? Seems like your doing everything right, is it by chance budding?

 

[minireef guy]

I haven't noticed anything near the flesh on the skeleton. It's definately not budding. I've noticed something else over the weekend. For brief periods it will open its "mouth" exposing its white insides. This has happened only twice that I have seen and not for more than 5 minutes. Usually when bothered. It still expands completely during the day and accepts food(squid).