montipora turning white

[msb27]

Title says it all. Not sure on the scientific name but it has the apperance of deer antlers. I actually have two pieces, one on each side of the tank. Both pieces are about 1 year old. Both have grown quite a bit since I have had them. Only one piece is turning white, starting at the base and working its way up the tips Is this "bleaching". I have 330 watts of VHOs and both pieces are two thirds the way up in my standard 55. The Alk tested at 7 which I think is a little low. Calcium tested at 400-450. Any help would be appreciated.

Thanks Scott

[smiller]

Sounds like montipora digitata and sounds like RTN. Is the white area moving quickly? You can do a search and get a ton of info about it. There could be many reasons for this happening. You probably need to cut the coral above the bleaching area and remount it or you will likely loose the entire coral.

[msb27]

white area is moving very quickly!!!

[msb27]

After looking this morning, the entire piece is pretty much gone. I did search for RTN as you suggested and after reading I agree that was the case. I went ahead and disposed of the dying piece.

Scott

[smiller]

It happens sometimes. I have lost a piece or two that RTNed before I had a chance to do anything about it.

[mirski57]

Have you changed salt mixes recently? I've heard of temporary bleaching when the salt mix is different.

[dougchambers]

Scott,

How old are your VHO bulbs? We started seeing some bleaching and color loss at the 11.5 month mark on our URI bulbs driven by an IceCap.

Doug

[msb27]

Bulbs were put into use in July 2002.

[dougchambers]

Scott,

What type of ballast are you using? You could be seeing the same thing we did at the 10 month mark. Many people swear by changing their VHO every 9-10 months even with IceCaps.

Doug

[msb27]

I use the ballast from hellolights. No change in salt mix.

Scott

[coraladdict]

I lost mine due to relatively high nutrient level,I had stopped skimming.

[smiller]

According to Bornemann's book there can be 20 or more reasons for an SPS suddenly going RTN. If everything else looks good I wouldn't sweat it too much.