SPS Corals losing color

My SPS are doing fine they just look faded. My birds nest coral is doing amazing I have seen amazing growth with it, and my montipora is still opening polyps but it is white. i know for a fact light is not the problem because they both have high light they just don't look as colorful as when I bought them. My water parameters are, Calcium 400ppm, Alkalinity 143.2 ppm, Nitrates 0ppm, Phosphates .5ppm. Any help is appreciated. Thanks!

 

What kind of lights do you have? When was the last time you changed the bulbs?

 

I have a Kessil A150W

 

Its not even a year old

 

Would it be possible to post any pictures of the affected corals? Also, how long have you had the corals that are fading?

 

Ive had the corals for a few months now. The Monti Went from a brilliant blue to white and brown and the birdsnest actualy skeleton when from a brown with really bright green poylps to a light skeleton with lighter green polyps. But they both are growing like crazy, just want to figure out why they did this and how to get the color back

 

It it possible that the symbiotic zooxanthellae that the coral first arrived with was ejected and replaced by the dominant variety in your tank. There are many reasons for why corals don't stay the same color though...

 

If they have a faded look to them then try lowering them from the light. Depending on what lighting they were under from where you got them could take a while for them to acclimate.

 

Ok the montipora was lowered I will keep an eye on it and see if it gets its color back. Are my parameters a little low for the CA and Alkinity?

 

The calcium can up a bit. I shoot for 450-460 but dont do it quickly. Your calcium isn't an issue at 400, I just prefer it a bit higher. Can you post your alk reading in DKH? I'm not sure where your alkalinity is at and it's important. Post magnesium as well since it's vital to keep an equilibrium with calcium and alkalinity.