Large Birdnest Concern

[shellsea]

I have a birdnest about 14 inch diameter that is bleaching out from the inner growth. Now about 6 inches of white with outer 6 or 7 inches holding color. Did a minor blue light increase of about 10 percent recently and had an Alk swing up to 10dkh from 9dkh. Anything I should check or do at this time?

 

[steallife904]

This is common with LEDs on large sps colonys. the par cant get through the branches as well as flow so they bleach in the middle. The alk could be an issue though. I had an alk swing a few months ago and it knocked out about 75% of my coral.... Including a pink birdnest colony the size of a football. Had been growing and fragging it for 8 years.... gone.
So keep an eye on the alk and slowly bring it back and you should be ok. a 1 dkh isn't so bad. not much you can do about the inside bleaching. more light I believe is the fix, more fixtures that is or halide or t5.

 

[swk]

Large Birdnest Concern

Ime birdsnests are very susceptible to any alk fluctuations and are excellent "canary in a coal mine" type pieces to have in a tank.

They grow very large, very fast. They require a decent amount of flow, and unfortunately, with leds, shadowing is very pronounced and can have a dramatic impact on sps.

If it's enough of an issue to bother you, then solutions include adding supplemental t5's, adding led strips like reef brights, or if using a point source style of led lighting like kessil, ecotech etc, you can add another fixture. If using a panel style led, like reef breeders or sbox, maybe add another fixture as well.

Hope it helps.