Acid Demand Calculator
Advanced calculator combining pH and alkalinity adjustment using acid-and-aerate technique.
How it works
Primary: muriatic acid for TA reductionSecondary: aeration hours to off-gas CO2 and raise pH backCycles: Lower TA by max 10-20 ppm per cycle
- You enter
- Pool volume (gallons), current pH, current alkalinity (ppm), target alkalinity (ppm), target pH, acid type, acid strength %
- You get
- Initial acid dose, aeration duration (hours), retest schedule, pH drift warning, cycles needed
How accurate is it? Concentrated acid pours more effective for TA; never add acid and chlorine together; aeration critical to prevent pH crash; 24-hr waits between cycles.
These are estimates, not quotes. See How We Estimate.
Worked example
15,000-gallon pool TA 150 ppm (target 90), pH 8.1 (target 7.4): Add 117 fl oz muriatic acid to deep end in one spot, aerate 4-6 hours, retest after 24 hours.
Tap an example above the calculator to see it worked with live numbers.
Reference table
| Reading | Ideal range | Notes |
|---|---|---|
| Free chlorine (FC) | 2–4 ppm | Chlorine that is still working |
| pH | 7.4–7.6 | How acidic or basic the water is |
| Total alkalinity (TA) | 80–120 ppm | Buffers pH so it holds steady |
| Calcium hardness | 200–400 ppm | Protects plaster from etching |
| Stabilizer (CYA) | 30–50 ppm (salt pools 60–80) | Shields chlorine from sunlight |
| Salt (salt pools) | 2,700–3,400 ppm | Check your salt cell's manual |
When to use it
Lowers high alkalinity while controlling pH impact, using concentrated acid pours and aeration.
Addressing high alkalinity (>120 ppm) that locks pH high, chronic pH drift, seasonal water refresh, saltwater pool management.