What kind of algae is this?

[Chevy]

I recently took over this aquarium from my dad and have been bringing it back to life. This black looking stuff appeared and seems to be spreading. Any help would be greatly appreciated!

[Tired]

That looks like some sort of black cyanobacteria. It's a natural part of a new tank, and of a tank which has had its balance badly upset. 

 

What are your parameters? 

 

Also, your substrate is far from ideal. It's too large-grained, and will trap a lot of detritus. You really want sand, or nothing. 

[Chevy]

That makes a lot of sense. When I decided to take it over it was in pretty bad shape. I saved everything I could and have been doing as much research as I can.  I am a beginner and appreciate the feedback. I didn't think about the substrate in that way and will look in to it!