i used 3 20" shop lights from walmart for my 220. built the hood out of scrap wood and left over stain. total cost was about 20 dollars. lights arent super bright or anything but does the job.
Fluorex outside flood lights are relatively cheap and almost to much light but they are working out pretty well for me on the 240. Mine is from glass cages, shipping is a B$itch price wise but I'm pleased with mine so far, just for reference, I would get the overflow boxes built in and pre drilled and run a sump instead of anything else to avoid clutter in the tank...wish I had. I run 3 of those fluorex fixtures sitting a inch or so off the top ghetto style right now and they are 500watts each supposedly at a draw of only 65watts. You could get by with 2 probably so like $80 bucks but I went with 3 because my driftwood pieces are huge and it was leaving big shadows around them in parts ~Trent