Acropora turning white

[okayamapiper]

I have an acropora japonica that is going from deep yellowish green to a pastel green. It is not dying as I have excellent polyp extension and growth but it is just turning white. Recently I have raised salinity from 1.021 to 1.026 at about .01/day and increased illumination from 70W of LED to 140W. The spectrum is about the same though I added 6W or 380nm UV. Any idea what brought about the change? The tank is a 15 gallon. Other than the Japonica changing colors, all other corals are doing well and growing. Any ideas would be appreciated.

 

[ronnie]

Unstable parameters and a big boost in lights without proper acclimation.

 

[c_healy]

Try moving it to a lower light area of the tank.