In a 15,000 gallon pool, 1.3 lb (574 g) of stabilizer granules raises cyanuric acid (CYA) by 10 ppm. Taking fresh water from 0 to 40 ppm needs 5.1 lb (2.3 kg). Liquid stabilizer is weaker by weight: 0.47 gal per 10 ppm.
| Change | Granules (99%) | Liquid (25%) |
|---|---|---|
| Raise 10 ppm | 1.3 lb | 0.47 gal |
| Raise 20 ppm | 2.5 lb | 0.94 gal |
| Raise 30 ppm | 3.8 lb | 1.4 gal |
| Raise 40 ppm | 5.1 lb | 1.9 gal |
| Raise 50 ppm | 6.3 lb | 2.3 gal |
| CYA 40 → 70 (salt pool) | 3.8 lb | 1.4 gal |
Add
5.1lb
of Stabilizer granules (cyanuric acid 99%)
81 oz2.3 kg
Raises CYA from 0 ppm to 40 ppm in 15,000 gal.
Check the product label. Strengths vary by brand, so enter the % printed on yours. Add one chemical at a time, into the water, and never mix chemicals.
Save this test and get reminded when it is time to retest.
Pool Calc for iPhoneComing soon to the App StoreGranules dissolve slowly. Put them in a sock or the skimmer basket with the pump running, and don’t backwash for a week. CYA takes several days to show fully on a test, so don’t top it up before then.
Overshooting is the expensive mistake: nothing you can add lowers CYA, only replacing water does. If you are unsure of your volume, add three quarters of the dose, wait a week and retest.
Manual chlorine pools usually run CYA 30 to 50. Salt water pools run 60 to 80, because the cell makes chlorine all day. Your chlorine target rises with CYA: see the FC/CYA calculator.
That is about the size of a 14 × 28 ft in-ground pool averaging 5 ft deep (about 14,660 gal). 15,000 gallons is a typical backyard pool. Measure the volume once rather than trusting the builder’s brochure: an error of 20% in gallons makes every dose 20% off. The pool volume calculator takes a minute.
1.3 lb of granular cyanuric acid per 10 ppm. From 0 to 40 ppm: 5.1 lb.
Granules can take several days to a week to dissolve and register on a test. Wait a week before adding more.
Only by replacing water. The drain and refill calculator shows how much.