[A643578]

This stuff is covering my whole tank.

 

[Amandas tank]

Oh no. I think that is Blue Green Algae.
http://www.plantedtank.net/articles/Algae-Common-Types/3/

 

[Diana]

Sure looks like Cyanobacteria! (AKA Blue Green Algae)

Note the Oto is above, not eating it. They do not.

 

[A643578]

Checked nitrates with API master test kit. 0 Nitrates. Upped my NO3 dosing since yesterday.

Using cidex/excel to kill this stuff...