My corals don't like my new light!

[Tigerbarb]

Recently, I ordered a t5 light and it arrived not too long ago. For about a week I'd say, I've been running it with 2X24 watt HO t5's, and at night I have been running the LED moonlights. The fixture has 4 bulbs, but I want to let my corals adjust so I am only running 2 of them. However, the zoanthids don't seem very happy and the mushroom corals are shriveled up. Since the tank is stable and there hasn't been any changes other than the light, I am assuming the corals are unhappy because they are still adjusting. After all, they went from 65 watts of PC to two HO t5's. I will check the water quality though. How long should it take for my corals to adjust? Should I be worried?

[MCHRKiller]

The 2x24watts is much more intense lighting than they were accustomed to with the PC fixture...it will take them a week or two to adapt. You could also try moving them further down onto the rock or raising your fixture a little to take some of the intensity down.

[Tigerbarb]

Oh okay, that makes sense. Thanks MC. I'll try moving the corals down lower.

[kaybee]

In addition to lowering the corals and utilizing half of your lights you can also reduce the photoperiod and then incrementally increase it back.

For example if you normally run your lights for 9 hours, run them for 4 hours and increase the photoperiod an hour each week until it matches the original photoperiod. This will give the corals a chance to photo-acclimate.

[Tigerbarb]

Good point, I was just thinking about that. I won't run the lights as long tonight.