Just stumbled on this while looking for new basement workshop lights... 6500K - 35 Watt - LED bulb with standard socket. The bulb is about 8" long. Would likely work great in one of those longer aluminum reflectors (see other photo below). For comparison sake, I'm currently running 30 Watts of LED over a 60cm (20 gallon) high tech with stems and a monte carlo carpet and has proven to be a sufficient amount of light. However, my setup is 3 separate lights spread across the surface area. This light would be concentrated in one area, unless you run two of them and suspend the lights a foot or so above the water surface to lessen the effective output on your system. Don't remember the rules on the forum and if outside links are allowed, but they're on Amazon. Just search for "35W Daylight LED Corn Light Bulb for Indoor Outdoor"