Pick a pump, set its controls and a run time, and see how much it pumps.
Strong-base (NaOH + KOH) addition into the feedwater tank.
Idealized estimate: treats the feedwater as unbuffered and ignores its alkalinity, dissolved CO₂, and temperature (uses 25 °C). Real buffering will make the actual rise smaller — this is an upper bound. SDS composition is a range; confirm the product's actual NaOH/KOH % and SG.
Caustic output % = multiplier × sulfite output %, where output % = stroke × frequency ÷ 100.
flow = rating × (stroke/100) × (frequency/100), max at 100/100.flow = rating × (setting/360), max at 360.flow = (GPD÷24) × (speed/100) — GPD rating pending.gallons pumped × SG × (%active/100) ÷ vessel gallons × 1,000,000. At SG 1.0 / 100% active this is ppm of product as-fed; enter the product's specific gravity and active % for active-ingredient ppm.