- 1). Measure about a half-cup of copper sulfate crystals and pour them into your toilet bowl.
- 2). Flush your toilet and wait for the tank to refill.
- 3). Repeat steps 1 and 2 until you have used up the nearly all entire the two pounds of copper sulfate, except for the last half cup. Do not flush the last half-cup of copper sulfate down the toilet.
- 4). Allow the last half-cup to remain in your toilet overnight before you flush your toilet again. Make sure no one uses the toilet while the copper sulfate granules remain in it.
- 5). Repeat from time to time to keep your sewers clean.
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