My betta tank is a 20g with 2 x 40 watt 6700 warm bulbs hanging over it with chains from the kitchen ceiling. Its height adjustable, I used mac-tac shelf paper on it folded double to make a shade and conc. the light over the tank. I use the extra length to grow house plants on my kitchen sideboard. I bought the fixture at walmart for 16.00, but I bought the bulbs at home depot to get a warm temperature bulb. They also sell sylvania aquarium bulbs that will fit it. Look at my link below, you'll see how the lighting looks.