Robelle Pool Cyanuric Acid Stabilizer 2-Pack (1.75 lb ea) — Fast-Dissolving, Extends Chlorine Life

Robelle Cyanuric Acid pool stabilizer quickly protects chlorine by slowing its breakdown from sunlight, helping maintain sanitizer levels longer.

Robelle's 1.75-pound, two-pack cyanuric acid (stabilizer) is designed for in-ground and above-ground pools to extend the effective life of chlorine. Formulated to dissolve rapidly, this product raises and holds cyanuric acid (CYA) in the recommended 40–100 ppm range when dosed correctly. Use it after filling or shocking a pool, or whenever CYA levels fall below the target range. Always test water chemistry with a reliable kit and follow the included dosing chart to reach the desired concentration safely.

How quickly will this stabilizer dissolve and start protecting chlorine?

Robelle's formula disperses quickly when added to a circulating pool system, but complete dissolution and uniform distribution take time. After adding the product to the skimmer or pre-dissolving in warm water, keep the pump and filter running continuously for 24 hours to fully dissolve and mix the stabilizer.

• Add slowly into the skimmer or pre-mix in a pail of warm water for faster dissolution.
• Run the filter continuously for 24 hours to ensure even distribution.
• Avoid adding directly to still water pockets where granules may settle.

What dose should I use to reach the recommended 40–100 ppm CYA range?

Use a test kit to measure the current cyanuric acid level, then consult the dosing chart included with the product. As a general guideline, 6 ounces of this product will raise CYA by approximately 10 ppm in 5,000 gallons of pool water. For a new or recently refilled pool with little to no stabilizer, add 4 ounces per 1,000 gallons to move toward the 40–100 ppm target.

• 6 ounces ≈ +10 ppm per 5,000 gallons of water.
• New/refilled pools: 4 oz per 1,000 gallons to build initial levels.
• Adjust in stages and re-test rather than adding large amounts at once.

Where and how should I add Robelle stabilizer to my pool?

You can add the stabilizer directly into the skimmer while the pump is running, or premix it in a bucket of warm water and pour the solution into the skimmer for more controlled application. Ensure the filter is clean before adding to avoid trapping undissolved particles, and circulate the water for at least 24 hours to complete dissolution.

• Option A: Slowly add into a running skimmer for straightforward dosing.
• Option B: Pre-dissolve in warm water then pour into the skimmer for faster mixing.
• Clean the filter first and run circulation continuously for 24 hours.

How does using cyanuric acid affect regular chlorine and pH maintenance?

Cyanuric acid stabilizes free chlorine against UV degradation, meaning you can maintain a steady chlorine residual longer between additions. However, you still must monitor and maintain free chlorine at the recommended 2.0–4.0 ppm and pH at 7.4–7.6 to ensure effective sanitation and swimmer comfort.

• Stabilizer reduces chlorine loss to sunlight but does not replace routine chlorine dosing.
• Keep free chlorine at 2.0–4.0 ppm for effective sanitization.
• Maintain pH between 7.4 and 7.6 for optimal chlorine performance.

Who is this product for? Robelle 1.75-pound cyanuric acid two-packs are aimed at pool owners and service professionals who need a dependable stabilizer to protect chlorine from UV degradation. It's suitable for both in-ground and above-ground pools, especially after refilling or during periods of high sun exposure. If you regularly test and adjust pool chemistry and follow manufacturer dosing guidance, this stabilizer helps keep chlorine effective longer while simplifying maintenance routines.