To provide the correct dosing you will need to know the flow rate that your well pump puts out. Use the following steps to determine that rate.

1. Turn the water on by opening a faucet or other water outlet until the pump turns on.
2. Turn the water off and wait until the pump has filled the pressure tank and turns off.
3. Without using any other water, open a faucet and use a 5 gallon bucket or other measurable container to collect and measure all the water that comes out until the pump turns on.
4. As soon as the pump turns on, immediately close the faucet and time how long, in seconds, the pump runs to refill the pressure tank, stopping when the pump turns off.
5. Divide the number of gallons measured by the number of seconds, and multiply by 60. This is your pump flow rate in gallons per minute (GPM).

Example: If your pump runs for about 40 seconds, and you collect 5 gallons of water:

5 ÷ 40 = 0.125
0.125 × 60 = 7.5
Your pump flow rate is about 7.5 GPM

Actual solution strength will vary depending on your water chemistry, with 2.5 ppm of soda ash needed to neutralize each ppm of CO₂ in the water. Since most people will not have that measurement dosing will typically require some trial by monitoring pH levels and adjusting as necessary. For most applications you will end up injecting between 100 - 200 ppm of soda ash to achieve a 7.0 pH, so 150 ppm is a good starting point. To determine the solution strength needed to achieve this dosing, multiply the desired dosage × pump flow rate × 1440 (minutes in a day) to get the maximum daily dosage in ppm. Divide that total by the maximum daily injection pump rate (if you have an adjustable rate injection pump, use half the maximum daily rate to allow for easier adjusting), and that will be your solution strength in ppm. This can be divided by 1,000,000 to get solution strength in percentage.

Example: If your desired dosage is 150 ppm, your pump puts out 7.5 GPM, and you are using the popular adjustable Stenner 85MHP17 that has a maximum 17 gallon per day output:

150 × 7.5 × 1440 = 1,620,000 ppm maximum daily dosage
1620000 ÷ 8.5 (half max for adjustable pump) = 190,588 ppm solution strength, or about 19%

Once you have the desired solution strength, mixing it is simple. Since water weighs approximately 8.35 lb or 134 oz per gallon, simply multiply this number by the desired solution strength in percentage to determine how much soda ash to mix per gallon. Using our prior example, to achieve a solution strength of 19%, you would use 8.35 × 0.19 = 1.59 lb of soda ash per gallon, OR 134 × 0.19 = 25.5 oz of soda ash per gallon. During the trial period you will typically want to make small batches until you determine your final solution strength.

With your solution made, begin injection and monitor your pH. Check your results at the faucet farthest from the injection pump to ensure complete treatment. If your pH is too low, increase your solution strength or adjustable pump output rate. If it is too high, reduce your solution strength or adjustable pump output rate. Contin