I will be replacing the 55 watt bulbs with 36 watt bulbs, in my AH Supply lights today. That will leave me with 1.6 watts per gallon. I will soon find out what the difference is from 2.4 watts per gallon. I'm guessing I will have to gradually shift to lower light demand plants, and I am hoping that the algae will find the tank a lot less hospitable now.