oops! sunburnt corals........

crlkeep · 08-21-2003, 01:15 AM

I recently came into some extra money, so I decided to treat my tank to some new light bulbs. This is normally a good thing, except when the lights are a little older than should be.

I changed 800 Watts of lighting power all at once. I shocked and stressed a few of my SPS corals. I raised the lights off the tank by 6 inches, and things seem to have stablized. Any advice on what to do for possibly burnt corals.

By shocked and stressed, I mean that the tips stopped growing, and some started to die at the tip.

MontanaRocknReefer · 08-21-2003, 10:04 AM

First of all from what I have read corals don't get sunburnt as they produce a compound that acts like a sun screen to protect them as the wild coral colonies do at low tide and they are exposed!
Yours are more from bleaching and with the new lights means alot more light intensity. I would lower the corals to the bottom of the tank until they adjust and gradually raise them up higher or put your lights on a shorter photo period and gradually extend the time the lights are on!

rogerthmyers · 08-21-2003, 10:57 AM

Did you notice that the corals did this directly after you changed the lighting?

crlkeep · 08-21-2003, 05:55 PM

They are not bleaching, the tissue started to lift off the skeleton on some of the new growth tips. No zooanthalae in the tips yet, so they are white already.
Yes, it started the next day after changing the lights, and I moved the lights up, immpossible to move 3 year old acropora colonies with out destroying the reef.
Not all corals produce the compound necessary to protect them from intense UV light. In shallow low tide reef flats, this is a common characteristic to find, but most of, if not all the corals I keep have never felt ocean air, Except maybe the parent colony of the Green Table I have.
It is also suggested that corals can loose the ability to block UV, if they have gone extended periods without it. Hence flourescent lit aquariums, as MH can shed UV if not manufactured to block reduce the levels.
Thank you both for your opinions, they mean alot to me. It would seem that in the last 2 days, no more "dying off" has occured. I don't want to make this a reef restructuring project if I don't have to. But I will if it deems necessary.
Thanks again.