Check these LED
lights out.... Top of the line great quality and very easy to hook up.
scroll down the page. Guys in the club I belong to have used these for a while now with no issues. I have 5 of the triple lights on my 125 and the light is just right.
I would think that one of the triple would work on your tank.
If you have a old transformer laying around from like a cordless phone that will work to power these up.
I just picked up 5 more and I will be putting 3 on my 55 and 1 on the 20 gal