A microbial detection device and methods of use are provided. The device comprises a water-proof pouch that includes a first wall portion, a second wall portion, and a porous membrane filter disposed in the pouch between the first and second wall portions. The filter membrane divides the pouch into first and second compartments. A dry, cold water-soluble gelling agent is adhered to the pouch in the first compartment and an absorbent pad is disposed in the second compartment. A sealable sample port provides access to deposit a liquid into the first compartment.