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Spa Chemical Dose Calculator
Dichlor in teaspoons and tablespoons for spa gallons. Wait 20 minutes with the cover off, then retest.
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Pool & spa calculators
Volume, chemistry, heating, pumps, and pool costs, each with visible math.
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Bromine Dose Calculator
Bromine in ounces and teaspoons for spa gallons. Hot water favors bromine; target 3-5 ppm.
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Pool LSI Calculator
Langelier index plus distance from balanced. Inside -0.3 to +0.3 is safe; below corrodes, above scales.
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Pool Chemical Cost Calculator
Monthly, daily, and annual chemical spend from chlorine, acid, and other supplies. Compare before switching systems.
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Pool Shock Dose Calculator
Cal-hypo in pounds and 1-lb bags with cost for breakpoint chlorination. Shock at dusk; swim only under 5 ppm FC.
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Phosphate Remover Calculator
Remover in fluid ounces and 32-oz bottles with cost. Run the filter 24 hours and clean it the next day.
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Borate Dose Calculator
Borax in pounds and 4-lb boxes for 30-50 ppm borates, plus cost. Borates buffer pH but never replace chlorine.
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Calcium Hardness Calculator
Calcium chloride in ounces and pounds for plaster 200-275 ppm. Confirm LSI after dosing to avoid scale.
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CYA Stabilizer Calculator
Stabilizer in ounces and pounds to reach 30-50 ppm. Above 100 ppm only drain-and-dilute works.
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pH Adjustment Calculator
Muriatic acid in fluid ounces and cups to lower pH, with the warning that acid also lowers alkalinity.
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