What is this for an algae?

[Chepre01]

Hi guys,
what is this? Does not look like Dinos or Cynos.

It is dark intense rviolet, not "slimy" it is more of a fluffy consistence and can be removed easily manually?

 

[Timfish]

Looks like cyano to me. Cyanobacteria can grow in thick mats sometimes and not thin films depending on environmental conditions.

 

[Chepre01]

ah ok thx, always thought cyanos are kind of flat and slimy instead of fluffy areas. colour at least is the same