pour about a half cup of baking soda down the drain, and then pour in vinegar until it bubbles up to the top of the drain. I leave that for about 15 minutes, and then pour really hot water (not quite to boiling) down the drain. This will help disinfect the drain and clean it too.
DIY Drain-O: 1/2 cup baking soda 1 cup vinegar 1 gallon boiling water Carefully siphon all the baking soda down the drain. Pour in 1/2 of the vinegar, covering the hole so the fizz is forced down, not up (omit this for toilets, please!). Add the second half of the vinegar, following the same procedure. Allow to sit for 15 minutes or so, and then flush with an entire gallon of boiling water.
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