angel,
Cleaning the glass will make your tank looks better, temporarily, but I think you should try to isolate the cause of your algea.
Eleven hours of light for a FOWLR is alot. Cut back on lighting. How old are your bulbs? If you've been burning them for 6 months or so, it's time to buy new ones. (NO bulbs' light spectrum degrades over time and will promote algea growth.)
How much do you feed? A little once a day, or even every other day is really fine. Have you tested for phosphates in your tank? In your top-off water? Phosphates and silicates (in tap water) feed algea. If you have phosphates in the tank, do you have a crushed coral substrate? Do you vacuum/clean it regularly? Do you use a phosphate sponge in your filter? If it's in the water you use for top-offs.....use RO/DI water instead of tap.( or buy distilled water from Walmart, grogery store, etc.)
Jim