Brown, Red, and Green algae in Overflow

[Snookin]

I have a 90g mixed reef and its been set up for about 5 months. My display part of the tank has almost zero algae growth. But, my overflow is covered on the sides with thick sludge algae. Ranges in color from brown (mostly) to some green and red.

Question: Should I clean out my overflow of the algae if it is not visibly effecting my tank or will this come to hurt me in the long run? What do you all do?

The picture does not do justice, it looks like more algae in the overflow than this.

 

[RalphsReef]

The only algae I clean from my overflow is when it gets into the teeth and slows down drainage. You could buy a cover for the overflow or make one. That would cut the algae out by means of taking light out of the equation.