The lights that try to reproduce the spectrum of the sun tend toward the yellow. Yours could be intended for a marine aquarium. You need some of that light spectrum for a freshwater aquarium, and you need really bright lights for some plants. However, if you buy easy to grow, low light plants you don't need exotic lighting. Check out the aquarium department of WalMart; they have low prices on replacement aquarium light tubes, but the selection is sometimes limited.
If you're going to buy very many aquarium supplies, try one of the on line shops like Drsfostersmith.com. They charge shipping but no tax, and they have information on selecting the right aquarium light. While you're shopping, you may also want to buy a clay based substrate supplement like pure laterite. It makes the water cloudy for up to a couple of weeks, but the aquarium will eventually clear. I tried the stuff after many unsuccessful attempts at growing plants in Phoenix water. After using the substrate supplement and carefully selecting plant varities, I put all of my plastic plants in the garage.