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Backwash Water Loss Calculator
Gallons per backwash cycle and per month from filter GPM, minutes, and frequency, plus water cost.
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Capacity calculators
Measure pool and spa volume, fill time, and water loss before dosing anything.
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Freeform Pool Volume Calculator
Kidney and freeform gallons estimate from overall length, width, and average depth, plus fill cost.
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Oval Pool Volume Calculator
Oval above-ground gallons from longest axis, shortest axis, and depth, plus fill cost at your water rate.
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Pool Cover Savings Calculator
Gallons and dollars a cover saves versus uncovered evaporation at your water rate.
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Pool Drain Time Calculator
Drain hours and days from gallons and pump or siphon GPM. Check local rules on where drain water may go.
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Pool Evaporation Calculator
Weekly and period water loss in gallons from surface area and bucket-test inches, plus refill cost.
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Pool Fill Time Calculator
Pool gallons divided by hose GPM and hose count gives fill hours plus water cost. Time it with a bucket test first.
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Pool Gallons by Dimensions Calculator
Gallons from length, width, shallow and deep ends with a sloped-floor average, plus fill cost.
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Pool Volume Calculator
Measure length, width, and average depth to get pool gallons, liters, fill cost, and water weight. Every chemical dose starts here.
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Round Pool Volume Calculator
Round pool gallons from diameter and depth, plus fill cost. Verify Intex and Bestway printed capacity before dosing.
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Spa Volume Calculator
Spa gallons from shell dimensions plus fill cost. Small volumes need teaspoon precision, not gallon guesses.
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Water Replacement Cost Calculator
Full or partial refill cost split into water and sewer portions, because many utilities bill sewer on water use.
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