HUGE problem with hair algae!!!!

The mid-day break in lighting will be detrimental to your plants. Algae can use much lower levels of than your plants, and can begin photosenthysis much quicker than them too. So, pretty much you're just depriving your plants of light/food for an hour a day and letting the algae have one hour of "freetime" to keep growing since it'll be able to use ambient light in the room.
 
I had a hair algae problem in a 29 gallon heavily planted/high light tank. Six Florida Flagfish later and the problem is solved... Just my .02.
 
Without CO2 you are doomed to algae with high light. Excel is an alternative but I'm not certain it can do the job at that light level. Amano shrimp eat hair algae very well, but that tank is a problem - you cannot balance light/ferts/CO2 without having any carbon source - even Amanos would be hard pressed to keep up.
 
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