Coralline algae die off

[Trapper]

Has anyone heard of coralline algae die off associated with replacing old metal halide's with new ones (old blueline 10k 400 watt to Iwasaki 6500k 400 watt bulbs). I think I've read a thread on this before. Anyone? I did'nt burn the bulb's in either and I've noticed my sps corals starting to shift their coloration from bright blue to more of a tan coloration. Not exactly what I call an improvement.

[Great Reefer Man]

Trapper,

You really need to acclimate the tank to the new lights very slowly!!!! Going from a 10k bulb to a 6500K bulb epecially. Your coralline and your sps are probably in the process of bleaching

I would give the corals like 2-3 hours of light daily while slowly increasing the light back to your full normal duration.

Good luck!
Dennis