- 1). Cover the drain with duct tape. Leave a small section uncovered so that the pests can fly. Inspect the tape daily and discard it after it fills with adult drain flies. Repeat the process until you remove most of the adult flies.
- 2). Pour ice cubes into the garbage disposal. Turn the disposal on and allow it to break the ice. The ice helps to loosen the sludge in the drain.
- 3). Insert a long-handled steel brush into the drain. Scrub inside the drain with the brush to loosen the organic material. Clean the drain every three days until you remove the drain flies completely. Run hot water down the drain to help flush out the loose material.
- 4). Bring a pot of water to a boil. Slowly pour the boiling water on the sides of the drain to eliminate the drain flies.
- 5). Pour a commercial drain cleaner into the drain. Select a drain cleaner that breaks down organic material. Always follow the instructions on the drain cleaner to ensure that you use it properly.
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