Lighting Schedule causing coral color loss??

I have a 90 Gallon SPS dominated tank. I am currently running 2 250w MH on lumatek ballasts with 2 14.5k Giesemann Megachrome bulbs. I also have 4 48" h.o. T5s on an icecap 660 ballast. currently my t5s are running 1 uvl super actinic 2 ati blue plus, and 1 ati purple plus.
My t5s are ran 12 hours and my mh are ran 6 hours a day. I have had this lighting over my tank for around 1.5 years change my t5s every 6 months and my mh every 9.

Is it possible that this may be too much light for my corals. I have several SPS corals that have almost no color at all, but still have decent polyp extension and seem to be growing ok. I have a red planet the is a light brown and the polyps have turned completly white, I also have an ora valida that is the same color and the polyps have also lost color. My tank parameters have been rock solid every time that I test them and I just cant figure out the problem.

Tank parameters:

Nitrate 0 red sea algae control
p04 0.031 Hanna checker
salt 1.027 ref
ph 7.95 to 8.15 reefkeeper
cal 450 red sea reef foundation
alk 8.5 red sea reef foundation 9.0 api
mag 1495 red sea reef foundation 1400 elos

Some corals in my tank seem to do ok and have really good growth but I just cant seem to get really good coloring out of any of my sps corals everything seems a little pale in color to me. The only thing that I could think of is maybe photo inhibition. I run about half a cup of carbon changed monthly and gfo whenever my p04 seems to creep up a bit. Any help would be greatly appreciated.

 

I do not not believe its a to much light scenario we have here Kracer

I would suspect that your nitrate is higher than your test kit is indicating
and as a result of that, you have more brown Zooxanthellia residing in your corals feeding on the nitrates

how far above the water level are your MH lamps?
I am running 2 x 250 watt lamps over my similar sized aquarium, and run them for 11 hours each day , and my corals are colouring up, rather than browning out
this is why I suspect that lighting is not the issue with your SPS corals

you might want to try extending the MH light up time, by an extra hour for a week or 2 and see if that starts to make a difference?

also I assume your SPS corals are at various heights in your aquarium
if the ones placed lower are better coloured than the ones higher up, that might indicate light is the issue
but if irrespective of location in relation to MH lighting, all SPS corals seem to be losing colour, fading to brown, then excessive nutrients may be the issue

Steve

 

Thanks for the reply. The uv glass on my reflectors is about 7" off the water so that puts my bulbs around 10" off the surface of the water. My t5 are 5" off the water all with individual reflectors. My corals are at different heights but the ones that are the highest up in my tank seem to have the least amount of color so that is what made me think that it may be that they could be getting too much light. I have a pink birdsnest that I just moved to near the sandbed and it turned a light pink compared the really light brown color it had when it was higher up.
I have seen other tanks running 400 watt mh with no added supp and it seems that my tank to the eye looks brighter (I know not a good judge of light output but we don't have a par meter available)
I have tested my nitrates several times with the red sea kit and with an api kit and the highest that I have rear on my low level test was 0.75 ppm.