As pool water evaporates, minerals and contaminants (such as dust, sunscreen, pool chemicals, etc.) become concentrated, eventually making it difficult to maintain the chemical balance in your pool.
Don’t drain the water without a chemical analysis from a pool professional or pool supply store. Although opinions vary, if your total dissolved solids (TDS) exceed 1,500 parts per million (ppm) or if your calcium hardness exceeds 350 ppm (or about 20 grains), it may be time to replace some of the pool water.
Clean Pool Filters the Water-Smart Way
When cleaning your pool filters, don't let water flow into the street—this is a water-waste violation. Rinse your pool filters over landscaped areas instead. The fresh water from your hose will dilute the chlorine so it won't harm plants or grass.