Rainbow montipora stn?

[Fishhands]

Ive had this rainbow montipora for a little over 2 mos. As you can see its almost covered the whole plug. However, in last 3 days this has shown up. Ive searched for nudis and not found any. This is my only montipora so i dont have reference. Other corals are doing better than ever. Even a favia i forgot about and threw in the sump with no light for months. Is doing great in the display. The problem that "may" have done this is a large w/c that brought my salinity down .004 from 1.026-1.022. Like I mentioned all other corals are fine. I have since calibrated the refractometer. Could the w/c have done this and by slowly raising back up could this recover?

 

[nautical_nathaniel]

How deep is it in the tank and what do you have for lighting on the tank?

 

[Fishhands]

How deep is it in the tank and what do you have for lighting on the tank?

40 breeder 8" deep. 4 bulb t5 (3 b+,1 c+) 7" off tank. So 15" total away from light. Too far? Too close?