Well I think the 2213 is to much for a 7.9 gallon and the 2211 to. If you want to go external filter then I would get the EHEIM aquacompact 40 or the 60.
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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