Reagent container and canister for use in an automated microbiological analyzer

A cup-like broth container having a generally octagonal cross section, an open top surface, and a closed bottom surface, the container comprising four mutually opposed pairs of connected sidewalls with a protruding rib formed on each of four perpendicularly opposed single sidewalls, said broth container further comprising four Y-shaped clamping ridges, each ridge having one leg portion and two extending arm portions, wherein each leg of the Y-shaped clamping ridge is attached to and extends outwardly from a single one of the four sidewalls located between the four sidewalls having a protruding rib.