0.01 grams (10 mg) per gallon of 52-58% CalHypo powder will give you 1-2 PPM chlorine (example ~0.3 grams per 30 gallon reservoir)
0.002 grams (2 mg) per liter of 52-58% CalHypo powder will give you 1-2 PPM chlorine (example ~0.28 grams per 100 liter reservoir)
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