Decide when elevated total dissolved solids (TDS) warrants draining or dilution

Steps

1. Test TDS and compare it to the pool's starting fill-water TDS baseline, since TDS is cumulative and only meaningful relative to that baseline.
2. Recognize that most public health codes do not set a hard maximum TDS requiring drainage — commonly cited action points (e.g., roughly 1,500–2,000 ppm above the starting fill-water TDS) are industry/manufacturer rules of thumb, not a universal regulatory threshold.
3. For salt chlorine generator pools, account for the salt itself, which raises TDS by design into the low thousands of ppm — do not treat that expected salt contribution as an out-of-balance condition.
4. Check whether the specific TDS meter/method being used double-counts salt or other dissolved minerals before deciding a drain is warranted.
5. If TDS is genuinely excessive and causing symptoms (poor sanitizer efficiency, persistent cloudiness, scaling despite balanced LSI inputs), plan a partial drain-and-refill and re-balance all other parameters afterward.