Reverse osmosis vs enzyme-based CYA reducers: Reverse osmosis wins for high CYA, but costs $400–600

Reverse osmosis is the only real option for lowering cyanuric acid without draining—it strips CYA and other solids, losing only 15–20% of water. Enzyme-based reducers are unreliable, lowering CYA by 20–30 ppm at best, often doing nothing. If CYA is over 100 and you can’t drain, reverse osmosis is worth the cost; for moderate levels (60–80), just stop using stabilized chlorine and let dilution handle it.