Whats going on with the zoas

I need some help figuring out what is going on with my radioactive dragon eye zoas. Recently some of these zoas have lost their color and seem to be withering away. They still open and close but just seem to be on deaths door step. I have included some pictures so that hopefully someone will have an idea of what is going on and maybe have some ides to keep me from losing the whole colony.

These zoas have been kept under a 300 watts of metal halide in a 55 gallon rectangular tank that is 20 inches deep with the top portion of the zoa colony about 10 inches below the light source.

My perimeters are:
Alk: 125.3
Ammonia: 0
Calcium: 480
Kh: 7
Nitrite: 0
Phosphate:0
Salinity: 1.0215
Nitrates: <5
Ph: 8.4
Temp: 80

 

How long have they been that close to that much light? I may be wrong but it sounds like they are being burned and the color change is a morph in response to the intense lights.

edit* Your sg looks a little low to me as well. I'd slowly raise it 1.025

 

They have been under the metal halides since about the last week of February, prior to that they were under 220 watts of vho. I took the metal halides off the tank last night and put the vho's back on just as a precaution. However I have positioned some of the polyps that have detached from the colony in different parts of the tank with different light exposures (when I was using the metal halides) and some of the polyps with low light exposure have lost their color also. This is displayed in the picture with the couple of individual polyps. All of the other mushrooms and ricordea are doing great, many have already split and doubled.

 

raise your Sg to atleast 1.023-1.025. maybe lower the colony 6" down lower and off to the side. also do a 10-20% water change.. may be your low on trace elements, etc.. give it a try.. nothing to lose..

 

Is there any diseases or parasites that could be causing this problem? Should I consider cutting away the affected polyps and if so what are the chances of the rest of the colony developing this same problem?

I will be adjusting the perimeters to the recommendations also!!!!!!!! Thanks.

 

Also should I consider using a coral dip as a treatment?

 

KH Needs raising a little bit aswell as your SG. Try feeding them a bit of brine shrimp or cyclopeeze too, just give them that little bit of extra energy

 

hey.... i had a maybe similar experince. my salanity is 1.025 and my meq was 5 and i lost all my zoos they slowly closed up and died every single one. they went from thriving to dying over a period of about 3 months. i tried everything moving the coral down.... up.... water changes dipping.

i also looked for nudi

maybe its a chemical war fare.... what are the other corals you have in your tank?

 

Yes, I am leaning this way also. LPD154 Do you use carbon or other media for toxin removal?

 

At the moment I'm not using any mechanical filtration.

Could I have chemical warfare between a few mushrooms, a green ricordea, and the zoas? There is plenty of separation between all of them.