Drain and refill is the only real solution for high TDS.

That’s the short answer. If your TDS is actually too high (over 2500–3000 ppm is generally where it starts mattering), the only practical way to bring it down is to drain a portion of the pool and refill with fresh water.

Most pool owners worry about TDS more than they should. Unless you’re running a commercial pool or seeing actual problems like cloudy water, scaling, or chlorine becoming ineffective, it’s fine to ignore it. No chemical additive, filter, or magic puck will meaningfully reduce dissolved solids. Reverse osmosis truck services exist but cost a fortune and aren’t worth it for a residential pool.

So unless you’re battling real issues, don’t bother. If you must, drain a third to half the pool and refill. That’s the whole playbook.

Save the worrying for your pH.