Is this algae?

[jge0]

Please see the pictures below. I am seeing it on the side of aquariums, beneath the surface. Is this algae? Any advice on how to remove them? Thank you!

 

[charliebankston]

It's brown diatoms (algae)
https://modestfish.com/brown-algae/

 

[fishwonder]

You can just run a razor blade down the side of the glass to remove it.

 

[charliebankston]

You can just run a razor blade down the side of the glass to remove it.

Don't use shaving cream tho

 

[fishwonder]

Don't use shaving cream tho