If it has a plastic rim the bottom of the glass doesn't touch the surface it is suspended. It should be fine if all the plastic is supported and it is level. Maybe spread out substrate evenly and don't get to heavy of drift wood or rocks.
So a guy walks into a Pet Store
Guy: "I have Algae on my drift wood!"
Pet Clerk: "Take two Plecos and call me next week."
EHEIM Classic 2213
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