For Proteus spp - Aerobically at 37°C for 4-6 hours. For other Enterobacteriacaea - Aerobically at 37°C for 24-48 hours

Based on Christensen’s Medium this medium is generally used to detect rapid urease activity of Proteus spp although it can be used to detect urease activity of other Enterobacteriaceae. When used for the later purpose it is necessary to increase the incubation time to as long as 48 hours.