Best way to clean residue off old glass tanks?

[skjl47]

Hello; Looks good . You appear understocked at this point. The big flower pot is there for a reason??

 

[landmineyouth]

The flower pot is merely ornamental and might function as a cave. I am understocked at the moment because the tank is new and cycling and I dont want to over-do the bio-load. The fish will be big... one day.