this might not be in your budget but you can try diy LEDs from rapidled with 30 degrees lens which will penetrate your 30" height but you have to hang it though. you can use dimmable driver to control brightness too.
Placing them front to back might be an option, I don't have any experience owning LEDs personally so I just wonder if that method would disperse the light properly. They don't have to cover the entire 7 ft. I was probably going to go with two 3 ft fixtures.
Front to back could be just fine with the right LED. Folks use smaller LED fixtures a lot for reef tanks. Some of those fixtures can be expensive though.
