How much stabilizer for a 10,000 gallon pool?
A 10,000 gallon pool needs about 2.5 lb (40.1 oz) of granular stabilizer to raise cyanuric acid from 0 to 30 ppm. At 30 ppm, keep free chlorine at least 2 ppm.
How to work it out
- In short: stabilizer is added by weight — the rise you want times the water in your pool.
- Rise: 30 − 0 = 30 ppm
- 30 mg per litre × 37,854 L = 1,136 g of cyanuric acid = 2.5 lb (40.1 oz)
- Chlorine to keep at 30 ppm CYA: about 2 ppm (Trouble Free Pool’s 7.5% convention; CDC minimum with CYA: 2 ppm)
A 10,000 gallon pool after a fresh fill has no stabilizer, and on a sunny day its chlorine can vanish by mid-afternoon. A few pounds of cyanuric acid fixes that for the whole season, as long as it isn’t drained or splashed away.
Adjust for your project
- CYA rise
- 30 ppm
- Free chlorine to keep at that CYA (7.5% convention)
- 2 ppm
- Per 10 ppm in this pool
- 13.4 oz
- Granular stabilizer dissolves slowly — often days. Follow the label (many say the skimmer, a sock, or a bucket), keep the pump running, and don’t backwash for a few days. Test CYA again after the dissolve time; the MAHC asks public pools to retest 24 hours after adding it.
- Stabilized chlorine adds CYA as you go: trichlor tablets about 0.6 ppm per ppm of chlorine, dichlor about 0.9. Using them? Aim lower and let them make up the rest.
10,000 gallons from 0 ppm, by target CYA
| Target CYA | Add this much stabilizer | Free chlorine to keep at that CYA (7.5% convention) |
|---|---|---|
| 20 ppm | 1.67 lb (26.7 oz) | 2 ppm |
| 30 ppm | 2.5 lb (40.1 oz) | 2 ppm |
| 40 ppm | 3.34 lb (53.4 oz) | 3 ppm |
| 50 ppm | 4.17 lb (66.8 oz) | 4 ppm |
| 60 ppm | 5.01 lb (80.1 oz) | 5 ppm |
| 70 ppm | 5.84 lb (93.5 oz) | 5 ppm |
| 80 ppm | 6.68 lb (107 oz) | 6 ppm |
30 or 40 ppm?
Thirty ppm takes 2.5 lb of granular stabilizer — exactly the rate on the label quoted above. Forty ppm takes about 3.3 lb. The choice depends on how you chlorinate:
- Liquid chlorine or cal-hypo: they add no CYA, so set it where you want it — 30–50 ppm is common — and it will only drift down with splash-out and backwashing.
- Trichlor tablets: they add about 0.6 ppm of CYA per ppm of chlorine, so start low (about 20–30 ppm). Two or three tablets a week in this pool add roughly 8 ppm a week.
- Salt cell: many owners run 60–80 ppm — about 5 to 6.7 lb from zero — so the cell keeps up with the sun.
- Above-ground pools with a sand filter lose granules if you backwash too soon; hold off for a few days.
The chlorine each level needs is in the chlorine and stabilizer calculator; for a bigger pool see how much stabilizer for a 20,000 gallon pool. If you prefer stabilized chlorine for the first few weeks, how many chlorine tablets for a 10,000 gallon pool shows how fast it builds.
Different size? Use the full Pool Stabilizer (CYA) Calculator.
What you’ll need
- Stabilizer / conditioner (cyanuric acid)Budget price
Shields chlorine from sunlight. Dissolves slowly — follow the label (many say a skimmer or a sock), and don’t backwash for a few days.
See options on Amazon (opens in a new tab) - FAS-DPD drop test kit (chlorine, pH, TA, CH, CYA)Mid-range price
A drop-count kit reads free chlorine to 0.5 ppm (or 0.2 ppm), plus pH, alkalinity, calcium and stabilizer. Every dose on this site starts from a test, so this is the one thing worth buying first.
See options on Amazon (opens in a new tab) - Digital scale (to 5 kg / 11 lb)Budget price
Weighs granular chemicals to the ounce. Use a dedicated scale — never the one you cook with.
See options on Amazon (opens in a new tab)
As an Amazon Associate we earn from qualifying purchases. Links to products are affiliate links — they cost you nothing extra and help keep these calculators free.
Frequently asked questions
How much stabilizer for a 10,000 gallon pool to reach 40 ppm?
About 3.34 lb (53.4 oz) of granular cyanuric acid from zero.
How much liquid stabilizer for a 10,000 gallon pool, 0 to 30 ppm?
About 120 fl oz (3.8 qt) at one brand’s label rate of 4 fl oz per ppm per 10,000 gallons — check your bottle.
How much stabilizer for a 5,000 gallon pool to reach 30 ppm?
About 1.25 lb (20 oz) of granular.
Other common sizes
- How much stabilizer for a 20,000 gallon pool — 6.68 lb (107 oz)
Sources
- Leslie’s — Pool Stabilizer (cyanuric acid) label (opens in a new tab) — 100% cyanuric acid; 2-1/2 lb per 10,000 gallons raises CYA by 30 ppm.
- Leslie’s — Instant Pool Water Conditioner Plus (liquid) label (opens in a new tab) — 4 oz in 10,000 gallons raises CYA 1 ppm; 1 gallon raises it 32 ppm per 10,000 gallons.
- CDC — Model Aquatic Health Code, 5th edition (2024), code (opens in a new tab) — Free chlorine minimum 1.0 ppm (2.0 with CYA, 3.0 in spas); pH 7.0–7.8; CYA at or below 90 ppm; CYA:FC above 45:1 is an imminent hazard; TA 60–180 ppm; turnover tables.
- CDC — Model Aquatic Health Code, 5th edition (2024), annex (opens in a new tab) — CYA reduces chlorine’s effectiveness; correcting total alkalinity for CYA by subtracting CYA ÷ 3.
- CDC Healthy Swimming — Home pool and hot tub water treatment and testing (opens in a new tab) — pH 7.0–7.8; free chlorine at least 1 ppm in pools (2 ppm with cyanuric acid) and 3 ppm in hot tubs; no CYA in hot tubs; test twice a day.
- Trouble Free Pool (hobbyist forum wiki) — CYA/chlorine relationship (opens in a new tab) — A widely used hobbyist convention, not an official standard: minimum FC 7.5% of CYA, SLAM (shock) level 40% of CYA, salt-water pools 5%.
- ICC Building Safety Journal (PHTA Recreational Water Quality Committee) — Trichlor: the dependable pool performer (opens in a new tab) — Trichlor is 90% available chlorine and adds 0.6 ppm cyanuric acid for each ppm of chlorine.
- CDC — Pool chemical injuries press release (2014) (opens in a new tab) — Never mix pool chemicals, especially chlorine products with acid; add chemical to water, never water to chemical.