GranuCult® prime Slanetz and Bartley agar acc. ISO 7899 is used for the enumeration of Enterococci in water and other liquids. The growth of the entire accompanying Gram-negative microbial flora is inhibited by sodium azide. Enterococci reduce 2,3,5-Triphenyl tetrazolium chloride (TTC) to give a red formazan inside the bacterial cell, and their colonies are thus red. Tryptose provides nitrogen, minerals, and amino acids, while yeast extract supplies vitamins. Glucose acts as the carbon source, dipotassium phosphate buffers the medium, and agar-agar is the solidifying agent.

SLANETZ and BARTLEY agar is suitable for the enumeration of Enterococci in water and other liquids by the membrane filtration technique.