ORA Red Planet receding at base

[LilFish]

My ORA Red Planet frag is receding from the base, the top 3/4 still has nice red tissue with good polyp extension but the base has turned gray and stony looking and lost its polyps.
I have it directly under my LED lights top of the tank in a biocube running Steve's LEDs at 45% which I originally had it in a lower position and slowly increased the lighting from 30->45 and have since moved it to its current location.
Do you think its getting too much light?
parameters: Ammonia=0, Nitrites=0,Nitrates=0, salinity 1.027, Ca=500, Mg1800, Alk=9dkH, temp=79F.

 

[KMench]

Can you post a picture?

 

[LilFish]

 

[KMench]

I’m no expert, but I would think if it was bleaching it would bleach from the top down because the light intensity would be greatest at the top. Any pest problems with your tank? How do your other corals look? With your nitrates at 0, the coral might not like the lack of nutrients in the water. What test kit do you use? How are your phosphates?

Sorry for the bombardment of questions. Just trying to help ;Bookworm

 

[LilFish]

All the other corals seem fine color wise and most are visibly growing although it is my first acropora, hence why I have it top and center. I tested with API for Am, Nitrites, Nitrates and Red Sea for Ca, Mg, Alk. I do not have a test kit for PO4 but would assume its low since I dont have any algae issues.....
I dose Red Sea Reef Energy twice a week, and feed small amounts of Mysis and/or Oyster Feast twice daily.

 

[LilFish]

I thought too much light would cause the whole body to bleach or fade but this is only the base. However the backside that is more shaded does not appear to have nearly as much recession