I would would just not scrub the back of your tank, and wait a tad longer to do your water changes until algae population picks up. A lot of people think algae is some terrible thing, but its all just in the cycle of life lemme see if i can find the article i read about that awhile ago. does your sand ever get that brown algae on it? They love that!
Yes, some algae is a cycle that you go through, but there are a lot of algae that will choke out and damage or kill your coral.