Pool-Calculator/formulas.md

2.4 KiB

Stabilizer

CYA Increase (ppm) = [Pounds of Stabilizer X 12] / (Pool Gallons / 10,000)

Adding Stabilizer

Target CYA = Current FC / 0.075

For Salt Pools

Target CYG (saltwater) = Current FC / 0.05

Dry Acid to Muriatic

1 pound of Dry Acid = 26 fl oz of 31.45% Muriatic 1.25 pounds of Dry Acid = 1 quart (32oz) of Muriatic 5 pounds of Dry Acid = 1 Gallon of Muriatic

Alkalinity Raising

Pounds of Sodium Bicarbonate (BP100) = [Desired TA Increase (ppm) * 1.4] / (Pool Gallons / 10,000)

Lowering pH (or readjusting pH after raising alkalinity)

3 options: Muriatic Acid, Acid Blue, Sodium Bisulfate/Lo N Slo

31.45% Muriatic Acid

Fluid Ounces of Muriatic = [10 fl oz * (Desired pH Drop / 0.2)] / (10,000 / pool gallons)

Acid Blue

Fluid Ounces of Acid Blue = [10 fl oz * (Desired pH Drop / 0.2)] / (10,000 / pool gallons)

Dry Acid or Lo N Slo

Ounces (by Weight) of Dry Acid = [13 oz * (Desired pH Drop / 0.2)] / (10,000 / pool gallons)

Increase pH

Ounces (by weight) of Soda Ash (Balace Pak 200) = [6oz * (Desired pH Rise / 0.2)] / (10,000 / pool gallons)

Adjusting pH Down after raising Alkalinity

Gemini says this should be done with a Matrix or Dynamic Algorithm, and the Algorithm sounds like the best option. However, instead of a "dynamic algorithm" like Gemini probably intended, I think several formulas might work fine. Simply put, we first check the input Total Alkalinity (as provided by ALEX), and see whether it's above, below, or inside the target range. If the input is below, we would run the formula to determine how much Alk. Increaser is needed to reach the target range, preferably as close to the middle as possible, and "log" that number, which is our new TA. Next, we need to figure out how to adjust for pH. We start with a simple formula: Base Dose (fl oz) = [Pool Gallons / 10,000] * ([Current pH - Target pH]/ 0.2) * 10

TA Lowering

Total Alkalinity and Adjusted Alkalinity

Total Alkalinity is water's ability to resist pH changes. TA is the sum of all the concentrations of chemical ion species in your pool water that can react with (or consume) a hydrogen ion (H+). Adjusted Alkalinity is the Total Alkalinity minus the CYA multiplied by Correction Factor, which is based on the pH.

However, since pools are usually between 7.2 and 8.2 pH, just use the following to get Adjusted Alkalinity: AA = TA - (CYA * 0.33)

Basically, keep TA at around 80-120 during the winter, and 60-90 during the season