"Treat the water with bleach once a month. This will help prevent algae growth. All you need is 1/4 teaspoon per gallon of water, or 2 to 4 tablespoons for a 55-gallon barrel. Beneficial microbes can also be used in lieu of bleach. One such product is Nutri-Life BAM3

Test the pH of your water once a month using a standard pH test strip. If the water is neutral or alkaline (aka "hard" water), add vinegar to bring back its acidity. For a 55-gallon barrel, you typically only need a couple of tablespoons to correct the pH balance. Vinegar is another option for lowering the pH"

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