Originally Posted by Leprichon
xxxI have a Corallife light fixture...It has 4 flaurecent bulbs...two are acti nic and two are daylight...they are on timers - the actinic I have set for a few hours in morn and at night (like sunrise and sunset)...and the daylight are for the time between (in the day)...
While I'm not sure if this has anything to do with your problem, and maybe I'm just misunderstanding what you wrote, but...
During the daytime hours, you should have all 4 of those bulbs on. You can turn on the actinics in the morning/evening to simulate sunrise and sunset, but leave them on while your daylight bulbs are on too. From how I read what you wrote, it sounds like when your daylight bulbs turn on, you turn off your actinics. Those actinics are giving your corals a lot of light that they need.
Regarding changing out PC
bulbs (I'm assuming it's a Coralife PC
fixture), I usually change mine out every 6 months. I think the recommendation is every 6-8 months, but will depend on how long you run them each day.