_This is very simple - just baking soda and white vinegar. You can also use lemon juice if you have that on hand! This works best on drains that are running very slow, but not those with standing water. If your problem is soap scum or other build up, this will break it up and get things moving again. It also works as a good deodorizer for kitchen drains.
Shake a bit of baking soda over the drain - about 1/4 of a cup or so. Push it into and around the drain, and then pour a bit of vinegar over it until you get a good bit of bubbling and the vinegar begins to pool in the sink.
Let this drain and set for 15-20 minutes and then flush with hot water. And as a bonus, you can also clean your sink with the little bit of mixture that'll be left at the top of the drain.
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Helping you keep your home clean with tips & secrets about homemade green cleaning recipes.