green algae?

It looks a bit like a satellite photo of Cleveland, unfortunately. I'm not sure what I am supposed to be looking at. Is it hairy? Soft? Coarse?

A few general things will help. Careful feeding, skimming, and maintaining calcium and alkalinity will help to inhibit the growth of nuisance algae and encourage coralline. Herbivores, like astraea, trochus and turbo snails are good for grazing the glass.
 
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