They're only expensive if you get the proper aquarium halide units. A double three foot would be around $70-80? so that's $140-160. I got my halide (shop unit) for $100, then the 6400k bulb was $60, so that's roughly the same price. It really depends on what you're going to be keeping in the tank; do you want plants, or just fish? If you're going heavily planted I would say go with the halides or T5's, but if it's not heavily planted stick with the fluoro's.