Dude,

I think what Bro Nano is asking is along the lines of why does most LFS put one single plecos with other fishes in their tanks rather than why they stock so little of them.

Well contrary to most people belief, they put them plecs there to eat all the dirt off i.e faeces and other leftover foods. Plecs don't eat faeces, and I don't know where anyone got that idea. They do eat leftover foods and some do help in clearing off algae.

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