Hello all. I'm planning to build a reef aquarium, and one of the problems I'm running into is simulating day/night light transition. There are actually expensive timed-dimmers that can do that to my VHO fluorescents, but they destroy the lamps. What I'm planning to achieve, is have the lights go off one by one at 15 min intervals. That is much better than having all 4 lights shut off suddenly (startling the fish + corals inside). I will use the IceCap 660 VHO ballast to power 4 4ft VHO lamps (110W each). The ballast runs fine any combination or number of lamps so thats not a problem. As with any fluorescent, there are two leads going up to each socket. All I would need to do then is break the circuit in both of those wires simultaneously. That will power the lamp off, and in 15 min the process can be repeated on the next light. In the morning, the lights would once again power up at these intervals. I haven't been able to find anything prebuilt (and affordable) for this simple type of use. I was thinking of using an ac relay with a simple plug in timer, but then I would need to know which relays are appropriate to make sure there is no interference to the lights. Anyone got any ideas? Btw, here is a link to the specs of the ballast if necessary: http://www.icecapinc.com/pdf/660.pdf