Do your hoods use normal incandescent screw in bulbs?(hopefully you do as thats the easiest way to upgrade)
If so you can pick up some Compact Florescent screw in bulbs to replace those. Most are spiral and they are not as good as the "U-shaped" bulbs but they will work. Most will tell you that you dont want the normal "soft white" or "warm white", you need a "daylight" bulb. Daylight is normally considered a 5000K-6500K(k=Kelvin). You want prob 30watts total for a minimum on a 10g using spirals, so that would be 2 ~15watt bulbe. You go by the real watt of the bulb not the "compares to a 75w" or "same light as a 75w", ect.. GE makes spiral daylight bulbs in 15w,20w and 26w, can be found at Walmart cheapest. Also Walgreens has Feit Electric spiral daylight bulbs in 13w/18w/23w and are cheap 4 bulbs for $10. The U-shaped ones are hard to find in daylight, I know at least 1 person having success w/ a normal soft white 2700k U-shaped bulb, but most would say to get daylight.
So you can buy a new hood of find a used one that uses the incandescent bulbs for pretty cheap then just replace the bulbs like stated above
If you have tube fluorescent bulbs then they are all the same watts depending on the length(should be a 18" 15w T8 bulb). So you basically are stuck, you can overdrive the light, search for "ODNO" to find info.
Or you can buy a new fixture, there are many brands and options(not as many for a 10G).
For cheap and DIY ODNO is an option for a flourescent hood, the most you get is ~2x the rated watts at 4x overdriven.
Or in my case I did not know about ODNO till the other day, I had a flourescent 15w tube hood. I did a little project where I took out the tube and replaced/rewired for 2 normal light bulbs. I used "aluminum reflective tape" and some 44oz cups to make an OK reflector. Cost ~$20 and now have 2x 20W GE 6500K spiral screw in compact flourescent bulbs.
Heres a pic of mine:
