zoanthids turning brown

[fishbait]

two months ago i purchased some beutiful green zoanthids. they have grown and spread like crazy, but in the last couple of weeks they have started turning brown around the edges. it started with only one polyp, and now has spread to all but one or two. they still seem to be healthy and expanding well. is this something normal for zoanthids to do occasionly? will they get there color back eventually? here is a pic shortly after i first purchased them.

they look a little brown around the edges in this pic. but, that was just how the picture turned out. my daylights just went out for the night. so, i will get a current pic tommorrow.

[bobby]

Zoos color depends on the lights you keep them under. I have some kriptonie zoos that have dulled since I bought them, but still look good. None of nine have changed to a diff color but I have heard of it happening. What kind of lights are they under now and what kind of lights were they under when you bought them?

[Bifferwine]

I agree with Bobby... Different lighting can change the symbiotic zooxanthellae composition inside corals. I bought this trumpet coral that had bright green heads, within a few months under my T5s all the green heads turned brown. Since I moved it under MH a few weeks ago, all the green heads have come back. If you change the lighting, it can change the colors. This is assuming that they are in fact still healthy and nothing else has changed about them except for their color.

[fishbait]

they were under a small t-5 fixture, at the bottom of a 55 gallon tank at the lfs. now they are under a 265 watt pc fixture with a really good reflector, that sits directly on top of my tank. the zoa's are about 1/3 up from the bottom. my tank actually looks brighter than the tank at the lfs that i purchased them from. but, i don't know how long the lfs had them under those lights, it could have been just a day or two before i purchased them.

[bobby]

Could be. I'm pretty sure I read a few times that MH brings out the best color of coral, and I think it's because it mimics the sun. Pretty sure, but not 100% positive.

[MikMcgyver]

Every time my snails knock the frags of zoas I have down to the sand bed they change color. I am guessing different light affects them....When I pop them back up top they go back to normal colors..

[ReefKeeper]

i have noticed in my zoas, that when i run 14-20k bulbs they look a LOT better than when they are in my display under the 10k's. i think the blue spectrum is something that they need to produce the crazy colors.

[Bifferwine]

That's for sure! My LFS has all their corals under 20K, and they look AMAZING. I get them home under my 10Ks and it's kinda blah. I'm definitely upping the Kelvins when I get new bulbs.