Can you identify this algae?

[marcogiglione]

 

[kharmaguru]

Looks more wiry than hair algae so likely some sort of turf algae. Sprouting directly from the rock could make it hard to control. Are the tops of your rock clear of it because you are pulling it or is something eating it?

 

[griss]

Agree, some sort of turf algae.

 

[Max_in_Tax]

Maybe rhizoclonium hookeri

 

[Max_in_Tax]

Actually maybe closer to Ulva flexuosa or Ulva intestinalis.

Pictures of those here.