120 ppm = 1 lb/1000 gallons - Veolia Water

120 ppm = 1 lb/1000 gallons By James McDonald, PE, CWT Originally Published: CSTN March 2005 R ule of Thumb: One pound of anything added to 1,000 gallons of water will give you 120 ppm of that substance. This is a very handy rule of thumb, and it is useful to understand why this is true. ................
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