Determine when to drain and refill your spa or hot tub. Based on bather load and water quality parameters to ensure safe soaking conditions. Regular water replacement is necessary to remove the build-up of unfilterable organic waste and dissolved solids.
The standard formula is (Gallons / 3) / Daily Bathers. For a 300-gallon spa used by 2 people daily, you should drain and refill every 50 days.
Eventually, the water becomes 'saturated' with dissolved solids (TDS) like skin cells, lotion, and chemical byproducts. At this point, the water becomes cloudy and chemicals lose their effectiveness.
Use a specialized spa surface cleaner or a weak vinegar solution to wipe down the shell. Ensure you rinse thoroughly and wipe away any residue before refilling.