Daytime, you have 300 watts in "bulbs", 80 watts in 10.0 uvb bulbs (assuming two 48" bulbs, otherwise 10 watts per linear foot), 100 watts for the powersun, and maybe 5 watts a piece on the five gallon uth's , for a total of 495 watts max. Drops to 135 watts at night. Any surge protector rated for 500 watts or greater will do.