Quick Reference Guide
Raising Levels
| Chemical | To Raise | Add |
|---|---|---|
| Free Chlorine | +1 ppm | Liquid chlorine, cal-hypo, or dichlor |
| pH | +0.1 | Soda ash (sodium carbonate) |
| Alkalinity | +10 ppm | Baking soda (sodium bicarbonate) |
| Calcium Hardness | +10 ppm | Calcium chloride |
| Cyanuric Acid | +10 ppm | Stabilizer/conditioner |
Lowering Levels
| Chemical | To Lower | Method |
|---|---|---|
| Free Chlorine | -1 ppm | Wait it out, or use sodium thiosulfate |
| pH | -0.1 | Muriatic acid or dry acid |
| Alkalinity | -10 ppm | Muriatic acid (add slowly) |
| Calcium Hardness | Any | Partial drain and refill |
| Cyanuric Acid | Any | Partial drain and refill |
Ideal Ranges
Keep your pool within these ranges for optimal water quality:
- Free Chlorine: 2-4 ppm (with CYA) or 1-3 ppm (without)
- pH: 7.4-7.6
- Total Alkalinity: 80-120 ppm
- Calcium Hardness: 200-400 ppm
- Cyanuric Acid: 30-50 ppm
Tips for Best Results
- Test before adding chemicals - Always know your starting point
- Add chemicals with pump running - Helps distribute evenly
- Wait between additions - Give at least 30 minutes before retesting
- Never mix chemicals - Add one at a time to the pool
- Add acid to water - Never water to acid when diluting
How I Actually Use This Pool Chemical Calculator
I keep my testing simple. Before I touch a single bottle, I run a fresh test so I know exactly where the water sits that day. That reading is the whole point of this pool chemical calculator, because every dose it gives you is built off your real numbers, not a guess. If your free chlorine reads 1 ppm and you want 3, I let the pool chlorine calculator tell me the ounces instead of eyeballing the jug.
The order I add things matters more than most people expect. I balance alkalinity first, then pH, then chlorine last, and I give each addition a good half hour of circulation before I retest. Chasing pH while alkalinity is still swinging is how folks end up dumping in twice what they needed. Slow and steady, one chemical at a time, with the pump running the whole time.
One habit that has saved me a lot of money: I always confirm my pool's volume before dosing. If your gallon number is off by even ten percent, so is every dose. When I'm unsure I re-run the numbers through the volume tool below and then come back here.