Does it vanish at night? May be spirulina?
Take some of it out and put it in two cups of aquarium water. Add 1 ml of H2O2 . If the water turns color, you have cyano. If not, may be spirulina or a type of hair algae.
Definitely seems bacterial to me as your plants seem healthy.
Take some of it out and put it in two cups of aquarium water. Add 1 ml of H2O2 . If the water turns color, you have cyano. If not, may be spirulina or a type of hair algae.
Definitely seems bacterial to me as your plants seem healthy.
