There are a cpl of options you have here depending on what you consider breaking the bank.
A 48 inch 2x55
pc fixture is about $120.00 at Big Al's. THis will give you 2wpg (approx) of
pc lighting (more efficient tha N.O. lights)
If you have a 48 inch stripligh available you can go with a 2x55 bright kit from AHsupply for about $65.00 but you will need
PC bulbs also. This lighting will be better than the one above due to the quality of reflectors AHsupply uses (The absolute best
IME).
http://www.aquatraders.com sell really cheap Odyssea lighting (
PC) fixtures. You may wat to replace the bulbs. The have been know to be lousy with customer service and shipping takes 7-9 days but the prices are unbeatable and I've had no problems with them. (I have a 24 inch 65 watt
PC fixture and a 48 inch 4x55 watt
PC fixture and both work great).
Big Al's also has a triple tube 48 inch N.O. fixture. Thats descent lighting (not sure if the 48 inch tube is 40watts or 32) but if its 40 thats 120 watts with a better spread than a
PC fixture. It runs $99.99.
Last Option is a T5 double strip. (You would need 2 of these). 56 watts per fixture at ~ $48.00 apiece.
You are not going to find much for under approx $100.00. These are some viable options. Hope this helps.