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Conversion Formula:
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The conversion from parts per million (PPM) to grains per gallon (GPG) is used to measure water hardness. This conversion is essential for water treatment applications and understanding water quality.
The calculator uses the conversion formula:
Where:
Explanation: This formula converts the mineral concentration measurement from parts per million to the more traditional grains per gallon unit used in water treatment.
Details: Accurate water hardness conversion is crucial for proper water softening system sizing, determining treatment requirements, and understanding the potential for scale formation in pipes and appliances.
Tips: Enter the PPM value of your water hardness measurement. The value must be greater than 0. The calculator will automatically compute the equivalent GPG value.
Q1: What is the difference between PPM and GPG?
A: PPM (parts per million) and GPG (grains per gallon) are both units for measuring water hardness. GPG is traditionally used in water treatment in the US, while PPM is a more universal measurement.
Q2: What are typical water hardness ranges?
A: Soft water: 0-3.5 GPG (0-60 PPM), Moderately hard: 3.5-7 GPG (61-120 PPM), Hard: 7-10.5 GPG (121-180 PPM), Very hard: >10.5 GPG (>180 PPM).
Q3: Why is 17.118 used as the conversion factor?
A: This conversion factor is based on the definition of a grain (1/7000 pound) and the density of water, providing an accurate conversion between these two units of measurement.
Q4: When should I test my water hardness?
A: Test when moving to a new home, before installing water treatment equipment, or if you notice signs of hard water like scale buildup or poor soap lathering.
Q5: Can I use this conversion for all water hardness measurements?
A: Yes, this conversion is standard for calcium carbonate equivalent hardness measurements, which is the most common way to express water hardness.