Black Algae?

[leafs]

Some of my Amazon swords have a black spots on the leaves. It's only on my sword plants. My tank is a low light tank with various Crypts and Anubias that seem to be doing fine. Would anyone have any ideas as to what kind this is?

Thanks

 

[zig]

Why do you think its an algae? do the spots appear to be growing "on" the leaves or do the spots appear to be within the leaves themselves? how big are the spots?

Very hard to give a diagnosis......have you tried removing the offending black spots with your fingernail?

When you say the tank is a low light tank, how much light are we talking, and how big is the tank, and what make of light are you using, and how long has it been setup with plants?

 

[leafs]

They just look like black specks on the leaves. They really don't look like there growing and it doesn't seem to be getting any worse at the moment. It's a 29 gal and a 20 watt 6700k bulb. The tank has been set up with plants since last Feb. My swords are the only plants that I'm having problems with. They're still growing, but very slowly. I'm planning on upgrading my lighting so I can have more choices of plants.