4 Things to Know About Lowering Cyanuric Acid in Your Pool

Reverse osmosis is the only effective method for lowering high cyanuric acid without draining. A truck filters water through membranes that strip out CYA and other dissolved solids, then returns clean water, losing only 15–20% of the pool volume.

Enzyme-based CYA reducers are unreliable. At best, they lower levels by 20–30 ppm over a week with perfect use; at worst, they do nothing, and the chemistry is dubious.

Reverse osmosis costs $400–600 depending on pool size and location. This is cheaper than draining, refilling, and rebalancing, making it the best option when draining isn’t possible due to a concrete shell, high water table, or city restrictions.

For moderately high CYA (60–80 ppm), skip expensive treatments. Stop using stabilized chlorine and let splash-out and rain dilute the CYA naturally over time.