I have a 120 gallon reef that is over two years old. Lighting has always been power compacts (240 watts). I recently augmented the PC
's with T-5's (4 X 80 watts for a total of 320 watts). I added the T-5's to try to bring out more color of existing coral and possible allow for acquiring some SPS
. I kept the PC
's running on the same timetable and simply added the T-5 hood next to it. I know that light needs to be introduced slowly, so I only used 2 of the 4 T-5 bulbs (one daylight and one actinic) and only turned them on for a couple of hours per day the first week. Then increased to three the next. After two weeks, I'm having trouble with some of my coral. All water parameters test excellent and have not changed in months. Water temp is consistent at 82-84 (I'm in Florida), which is where it has been since the tank was set up. I have good ventilation and the additional lighting did NOT raise the water temp (I was careful about that). All fish are in perfect health. The only change is the additional light, so this seems obvious, but I thought I would ask. Last night I took the T-5's down and will only use the PC
's for the next few days. Most of the corals are doing just fine - only some are now looking bad. My candy cane (which is on the bottom and I've had for almost two years - has always looked great with some polyp division over time) is now showing absolutely no tissue expansion at all, my xenia starting dying the minute I changed my lighting, and now my blastmo merleti. Other corlas like zoos, mushrooms, and favia show no signs of change at all and appear to be just fine. Most of these are near the top and getting much light, but again, were not impacted. Here are my questions:
1) Would just a couple of hours of the additional lighting be capable of doing this?
2) It took almost two weeks to see signs of trouble. Does that make sense?
3) Should I do anything else besides returning to my PC
's for now? I really do not want to see the candy cane die. I think I caught it in time for the blasto merleti, but the candy cane looks bad.
4) When and how should I re-introduce the T-5's?