These are the targets Bluvo uses. They follow TroubleFreePool’s published method. The most important idea: your free chlorine target depends on your stabilizer (CYA). CYA protects chlorine from sunlight but also slows it down, so the more CYA you have, the more chlorine you need.
Free chlorine by CYA, chlorine pools
For liquid chlorine, bleach, cal-hypo, dichlor and trichlor. Round your CYA reading up to the next row.
| CYA (ppm) | FC minimum | FC target |
|---|---|---|
| 20 | 2 | 3–5 |
| 30 | 2 | 4–6 |
| 40 | 3 | 5–7 |
| 50 | 4 | 6–8 |
| 60 | 5 | 7–9 |
| 70 | 5 | 8–10 |
| 80 | 6 | 9–11 |
| 90 | 7 | 10–12 |
| 100 | 8 | 11–13 |
Free chlorine by CYA, saltwater pools
| CYA (ppm) | FC minimum | FC target |
|---|---|---|
| 20 | 2 | 3–5 |
| 30 | 2 | 3–6 |
| 40 | 2 | 3–7 |
| 50 | 2 | 3–8 |
| 60 | 3 | 4–9 |
| 70 | 3 | 5–10 |
| 80 | 4 | 6–11 |
| 90 | 4 | 6–12 |
| 100 | 5 | 7–13 |
Shock levels for each CYA are in the SLAM guide. With no stabilizer at all, sunlight burns chlorine off in hours: outdoor pools need CYA.
Everything else
| Reading | Pools | Hot tubs |
|---|---|---|
| pH | 7.2–7.8 | 7.2–7.8 |
| Total alkalinity (TA) | 50–90 ppm | 50–90 ppm |
| Calcium hardness (CH) | 350–650 ppm plaster and fiberglass; vinyl doesn’t need calcium | 100–250 ppm |
| Stabilizer (CYA) | 30–60 ppm; 60–90 ppm with a salt cell | 30–50 ppm (chlorine tubs) |
| Combined chlorine (CC) | 0.5 ppm or less | 0.5 ppm or less |
| Salt (salt cell) | The level in your cell’s manual, often about 3,200 ppm | |
| Bromine | – | 3–5 ppm |
Add chemicals one at a time, to the water, with the pump or jets running, and keep acid and chlorine at least 30 minutes apart. Always follow the product label.
Sources: TroubleFreePool, Free chlorine and CYA chart and Ideal pool levels. Bluvo is not affiliated with TroubleFreePool.