Cleaning Fuge - How much green should I remove

[b_james]

Every time I do a water change I'm never sure how much algae to clean out of the fuge. I have lots of cheato and grape cellurpa. Recently my sump has been developing lots of what looks like clumps of reddish (rust) color balls of algae that looks like cotton. Its quite dificult to remove as its all tangled up within the good algae. Lighting is on 24/7. Should I try to remove all but a small amount of macro algae or leave as much as I can in the fuge? Is the red cotton like algae bad?