The Pool Calculator takes care of all the math that might come up while you are keeping your swimming pool's water chemistry in balance, telling you exactly how much of each chemical to add. For background on what the various numbers mean, see Basic Pool Chemistry. If you have comments or questions about The Pool Calculator please write to firstname.lastname@example.org. For help with your pool try Trouble Free Pool, a swimming pool and spa care forum.
For the new and approved pool calculator see Pool Calculator.
NotesUnless you are shocking your pool, it is always best to add less than the full amount, wait a little while to allow the addition to mix thoroughly, and then retest to see where you are. Also, keep in mind that the volume of powders can vary from manufacturer to manufacturer.
Estimating pool volumeA wide by long by deep rectangularovalround (ignores length) pool holds.If the depth varies, use the average depth of the pool. A good approximation is the shallow end depth plus the deep end depth divided by two. Irregularly shaped pools can be approximated by estimating the average length and width and using rectangular.
Effects of adding chemicalsAdding of 5.25% bleach6% bleach10% bleach12.5% bleachtrichlordichlor48% cal-hypo53% cal-hypo65% cal-hypo73% cal-hypolithium hypochloritechlorine gas15.7% muriatic acid31.45% muriatic aciddry acidwashing soda or soda ashborax (20 Mule Team)sodium tetraborate pentahydratecaustic soda (lye)baking sodacalcium chloridecalcium chloride dihydratestabilizerliquid stabilizersalt willNote: pH calculations are not exact. These numbers are only suggestive of the relative magnitude of the pH change you can expect. Small changes, +-0.4, with pH between 7.2-7.8, TA around 80-120, and Borate near zero will be approximately correct. The further you go from those ranges the less these pH changes will correspond to reality.