Method for preventing the clogging of a drainage system

A method for preventing clogging of a drainage system having a trap, which comprises the steps of:

• (a) providing a device for use in a drainage system to prevent clogging of the drainage system which comprises:
• a container having porous walls;
• a composition located in the container for inhibiting growth of microorganisms in the drainage system which can clog the drainage system;
• a flexible member connected to the container for removing the container from the drainage system;
• and a stop means connected to the flexible member to prevent the flexible member from completely entering the drainage system to allow for removal of the container from the drainage system;
• (b) inserting and positioning the container having the composition into the drainage system such that the container is in the trap, wherein the trap has water in a low point and an opening for access to the low point, and wherein the composition is positioned in the water in the trap to prevent clogging;
• and
• (c) removing the container from the drainage system by grasping the stop means and pulling the container from the drainage system once the composition is no longer effective in preventing the formation of the microorganisms.