Brown Spots On Glass?

[Sharpy14]

Hey,
These have been apearing on my new tank which is filtered today and im sure its POOP isnt it? (lol)
Just wondering why because i never has these problem with my rio...

 

[Rogue4Fish]

Algae?

 

[MrCrabs]

I am sure its algae, just scrub it off and make sure you are not giving the tank too much light for too long, also make sure its not getting direct sunlight via. a window. Possibly check your Nitrates as if these get too high they are a source of food for plant/algae growth and can cause the undesireable algae to grow.