Lighting for 72 gallon

[Puffernewbee]

I recently bought a used 72 gallon Oceanic (48x18x21) bowfront tank and would like to venture into live plants with my community fish. I understand that I need around 2-3 watts per gallon which means I need 150 - 200 watts of light.
I hope this question does not sound to stupid but do I need to find a single 150 watt light or do two 75 watts accomplish the same thing?
Does anyone have a good suggestion as to a good light to get for this? I currently only have the single 48" 32 watt light that came with it. I have not seen 150 watt bulbs when looking at Big Al's. I am open to buying new lighting system but currently my funds are a tad limited. I would appreciate any suggestions.

Thanks

 

[djlen]

Go here: www.ahsupply.com/
I'm assuming that you have an existing hood over your tank now. Measure the inside dimensions of that hood. Look at the options that are available on that website and decide how much light you want over your tank. Then call the number on the bottom of the page or if you want to save some money call this number: 1 888 859-5106 and ask for Kim. Tell him what you want and what the inside dimensions of your hood are and he will tell you how/if you can retro-fit it with maybe 4X36, or 4X55(better for your deeper tank). Or 2X96 (an excellent option as well).
I don't own or have stock in this company. I just find them to be the best 'mom and pop' type outfit for lighting that I've ever dealt with. Their kits are complete and relatively easy to assemble.
[EDIT] I just noticed that they are closing on the 22nd for vacation. The whole outfit closes down for a few days each Aug.

Len