Coraline dying???

[The_Strobe]

The coraline in my tank is dying off and the corals do not look as good as they once did. I am noticing that there is new coraline overtaking some of my corals, (dead spots on the edges) I am sure that these are related, as is the calupra in the refugium not gorwing as fast as it once did. All water params are normal ALK=10 CA=480, PO4=0 NO=0...
The lighting is new 175W 12K This has been happening for a while now, I am doing regular water changes and all the usual things.

Any thoughts???

[reefnetworth]

IME, the 12K is possibly the culprit. it doesnt care to much for brighter/whiter light, more of a blue/purple such as a 14K or 0-3 Actinics.
i swaped my 14K to a 10K, and mine started turning whiter in a few weeks time with 4X96 watt 0-3 Actinics in use.
i went back to the 14K, and in 2 weeks noticed the colors returning to normal.