I dont know what this is

[Immasweetslover]

So my friends brothers tank started accumulating this and neither of us know what it is or how to get rid of it. I dont know if it's slime or biofilm or mold and unfortunately I dont have any water perameters since this isn't my tank or one I have acess to. Any help is appreciated in getting to the bottom of this mystery 

[Patrick_G]

I'm by no means an expert algae identifier, but to me it looks most like a form of hair algae. The stuff on the bottom might be black beard algae if it's not the same as the stuff on the plants. 

[nabokovfan87]

What is the lighting on the tank, lighting schedule, and the substrate?

I had a lot of similar issues with mine and I think a lot of the times it's down to nitrates over 20, dirty filters/substrate holding too many nutrients, and lighting.

Because of this specific type, you're going to have to manually remove it as best you can.  An old toothbrush helps a lot or a new dish sponge for larger surfaces.  Just make sure neither have any cleaners on them.