Algae bloom on plants

[Octopink]

Hey all! I'm experiencing a pretty bad algae bloom on my plants. I currently have a bristle nose pleco in quarantine right now to help with the stuff growing on the glass that I can't reach, but my plants seem to be suffering a good deal from it. Any suggestions? Is it even algea? I water change twice a week (30% then a 50%.) Tank is a 50 gal home to three goldfish and it's treated with Seachem Flourish once a week.

 

[Colin_T]

Some of it is brown algae and nothing major to worry about.

Some looks like blue green algae and is usually caused by excess nutrients, low oxygen levels, lots of red light, poor water movement.

What's the black stuff in the gravel in the pictures 7522 and 7523?

 

[Octopink]

Some of it is brown algae and nothing major to worry about.

Some looks like blue green algae and is usually caused by excess nutrients, low oxygen levels, lots of red light, poor water movement.

What's the black stuff in the gravel in the pictures 7522 and 7523?

Ok cool! Thank you Colin. I plan to improve the water movement and oxygen levels by adding an airstone and sponge filter soon.

The black stuff is poor taste. I added black, smaller grain gravel and larger, natural stone gravel mixed together? It's a questionable choice I made. Not really sure what my thought process was there.