Algae identification - treatment if necessary

[Schlagg]

I'm trying to identify if this is a problem and if it requires treatment. This is my first aquarium (started in February) and this started to persist about a month ago. Fish inhabitants seem ok, but firefish are pretty hardy.

 

[Slarti]

Does it go blackish and stringy after a while?

 

[Schlagg]

It's got a reddish/brown hue to it. Some of the strands can get pretty lengthy (4-10 inches)

 

[subbedout]

I have same issue, though mine hasn't been stringy (yet). Reddish brown hue to the sand in places.

 

[scooter31707]

looks like cyano in the 1st two pics. The 3rd pic is hard to tell, but it may be hair algae, dinos, or brynosis.