need help with button polyps

[scarter]

well heres the deal Three seperate colonies of button polyps are closed up and have been that way for about four months. They never open, but do not seem to be receding at all. The colonies seem to be as large as they were before this all happened.
I also have many smaller zoos that are doing fine. This only seems to effect the larger colonies. I have looked closely and do not see any sign of predators, such as nudibranches.
I have tried moveing them to higher light, less light, more flow, less flow. I cant seem to get them to open.
I have only one guess at to what happened. I am guessing, for lack of a better explination, that they were stung by another coral. Thats the only thing I can think of.

all of my parameters are in check.
200 gallon with 2x 400w MH 20,000k (no, they are not in direct light)
I keep a mixed reef.
please help me, these are large colonies and I do not want to loose them.

 

[sammy33]

I had a similar problem recently that ended up being ammonia. Have you tested for ammonia?

I had a fairly new Fiji Yellow Leather that had a large yellow sponge that was slowly dying. The sponge was well concealed as it just looked like part of the leather. This peice was about the size of half a lemon.

After a couple of weeks of zoathids not opening I finally figured out what was going on. The sponge had started turning grey/black at this point and smelled aweful when I finally pulled it out of the tank. I had not tested for ammonia. I only tested for nitrates, phosphate etc.

So to make a long story short...what are your water parameters?

 

[scarter]

all in check

 

[gflat65]

How old are your lights and what kind fo lighting are you running? I've got some Protopalythoa psammaphila (green buttons, but of the Palythoa variety instead of the Zoanthus variety) that did that to me once. They had been open for years, then all of a sudden, they closed up, but the colony slowly started disappearing. I changed just the VHO's and they opened back up and have never looked back. The inconsistency, though, is that I change all lights on a schedule and the schedule hasn't changed, so I can't explain why they closed then only to reopen under new bulbs, but haven't shown the same symptoms every time the bulbs need replacement...

 

[scarter]

400W MH and they are 4 mos old, they were closed before and after I changed my bulbs