Corals becoming pastel color?

[MarkoD]

I've noticed over the last month my corals have started turning a pastel version of their colors.

what would cause this?

calcium is a 430

alk is 8dkh

magnesium is about 1300

phosphates .02 (basically where they've always been)
nitrates: undetectable.

seems to be happening to all kinds of corals (sps, lps, zoas) and colors (reds, blues, purples)

only green seems to be maintaing color

[daplatapus]

What are you running for lights? Have you changed anything with them?

[xenon]

I would dim down the lighting a little and feed more. :)

Do you test for potassium?

[kien]

Some people strive for those pastelly colours in their SPS. Typically people will achieve this by starving their corals. Try feeding them more. An over abundance of light can cause them to lighten up and slowly bleach out as well.

Are you running an sort of probiotics on your system? BioPellets, zeoVit, prodibio, vodka/sugar/vinegar? All of those can starve your corals.

[kole]

the low phos and nitrates will cause this to happen. I am seeing it happen in my tank now because I am keeping low levels to fight off a GHA problem. Feed more.

[MarkoD]

I do feed my corals. I just adjusted the lights to be bluer. Running leds

[reefwars]

Try feeding later at night or in the morn while its still dark , I'd also lower the intensity of your leds wont hurt anything :)

[asylumdown]

My corals are pretty pastel from having low nutrients in the water. undetectable nitrates and 0.02 phosphate is pretty low. Is there any algae of any kind growing in your tank? If you've got super clean looking rocks and no macro algae of any kind, or if the growth rate of your algaes has declined significantly recently, it's a good chance the issue is nutrients.