Not exactly how this works, my friend. You need a simple cheap timer for your lights. When you turn my thingy ON the power gets cut off for up to an hour and then automatically turns the sump pump back on. I use it when feeding DT and really just when feeding the fish so the mysis won't go into the overflow and into the sump. It probably couldn't handle the amps of your lights... not that I know what kind of lights you have...