Colt coral shrinking up by end of light cycle -- too much light?

[bassinprof]

Hi everyone,
See the pics below, my colt coral has never looked that good but really seems to shrink down by the end of the day (second picture). Is this a sign that it's getting too much light? The lights are two Ecotec Radions on a 120 g tank. I know the lights can put out a lot of PAR but I've already dialed them down to 60% for 12 hours. My other corals look pretty good. Water quality is perfect.

 

[xcali1985]

How long have you had the coral?
What type of lighting did it come from? It is possible that you have shocked it by increasing the light intensity too fast.
Me personally I think a 12 hour photo period is long especially with mHs. I personally run my LEDs for 6. I read in a scientific magazine that stated that corals only needed 6 hours of light to recharge. Can't remember where I will try to find it.
If you had the coral for a while, has anything in the tank changed over the last couple days? Have you added any equipment, changed filter media, anything?
Is it near another coral that can possibly release toxins that would fight it?
I had a kenya tree that did the same thing, slimed completely out however before it completely slimmed out it fragged a branch off and I grew another full tree.

 

[bassinprof]

Quote:
Originally Posted by Xcali1985 http:///t/392789/colt-coral-shrinking-up-by-end-of-light-cycle-too-much-light#post_3489976
How long have you had the coral?
What type of lighting did it come from? It is possible that you have shocked it by increasing the light intensity too fast.
Me personally I think a 12 hour photo period is long especially with mHs. I personally run my LEDs for 6. I read in a scientific magazine that stated that corals only needed 6 hours of light to recharge. Can't remember where I will try to find it.
If you had the coral for a while, has anything in the tank changed over the last couple days? Have you added any equipment, changed filter media, anything?
Is it near another coral that can possibly release toxins that would fight it?
I had a kenya tree that did the same thing, slimed completely out however before it completely slimmed out it fragged a branch off and I grew another full tree.
I've had the coral about 9 months and the lights about 6. The coral did start to look bad when I got the lights so I'm guessing that's the problem but gee whiz how low can I dial down the lights without affecting everything else? Several other corals have really thrived under the lights. I guess I can stick it in a corner to see if it recovers. When the problem first came up I tried that and it didn't seem to make a difference but maybe I didn't wait long enough.

 

[snakeblitz33]

Set up an experiment...
Dial your lights down to 50% for 12 hours and look at the coral again over the course of a week. If no change then..
Dial your lights down to 45% for 12 hours and look at the coral again over the course of a week. If no change then...
Dial your lights up to 50% for 8 hours and look at the coral again over the course of a week. If no change then....
etc. etc. etc.
Gotta find a happy medium for all of your corals.