Need Help with MH Acclimation

[c9miles]

I recently set up a frag tank to grow out some of the zoos that are taking over my smaller tank. The new tank (20 long) has a 150 watt 10K metal halide, which is currently about 14 inches off the water's surface. I transfered some zoo frags to the new tank from the 72 watts of PC they were under before. I didn't have any window screen or a timer for the first two days, so I let the halide run about 6 hours a day and the frags opened and looked great. Now I have some window screen and I'm doing the layer method. I started with 4 layers and I'm removing a layer every 5 day or so. The frags won't even open now....I thought they need acclimating but it seems they aren't getting enough light. I'm not sure whether to continue the acclimation or just pull the screen off and let them have the full intensity? Any help would be great. Thanks.

Chad

[tims]

chad if they were already open fully before yo put the screen on , then just take it off... you do not have to run many hours of the MH is you are worried about them.. sounds like they already liked the increase of light..

[yardboy]

A lux meter would be nice in this case.

You can use a camera with a light meter if you have one. Put the lens right on the glass, aimed into the tank where the zoanthids used to be. Then do the same with it aimed at where they are now, with the screens and without it. Compare exposure times and match as close as you can. A coarse method, but it can work. My eye's pupil compensates for different light levels so it's hard to compare intensities by eye.
If you don't have a camera, my guess is that a 150W bulb 14" over a tank won't be radically higher than a set of PC bulbs 4" from the water, through the same depth of water.

[tdwyatt]

keep in mind that zoanthids will someties close up as a response to high lighting, water parameter changes, feeding responses, or just plain irritation to a earby neighbor. Some species will only open at night (only a few), and for the most part, most Zoanthids will do best under indirect lighting, especially if the light is from a MH lamp. Use them as understudes to HELP fill in the gaps for live rock surface coverage.


Personally, I would leave the screen in place for a bit, better to err on the side of caution rather than risk burning them up, though most Zoanthids can recover well from burns,


HTH

[Loverotties]

Yea keep them in for a little longer!

[c9miles]

Thanks for everyones replies. I think I'm going to keep a layer of screen on for another week or so, just to make sure they are ready for the light. Thanks for everyone's help.


Chad