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TheBlueprintof Water
Blueprint Pro · saves as a SystemWorked example · inputs locked

Cycle the makeup, predict the pH, read five minerals at the hottest surface.

Operating Case

Enter your system parameters. Results update automatically.

Tower pHPredicted from alkalinity, cycles, temperature, and CO₂ stripping. For an existing tower, enter the measured pH; measuring beats predicting.

From alkalinity, cycles, temperature, and CO₂ stripping.

TemperaturesHottest exchanger surface. The conservative check runs here.
°F
°F
Tower pH predicted, calcite at skin8.38 SI +1.80, scale forming
How far above atmospheric equilibrium the tower water holds CO₂. Real towers do not strip perfectly; about 5 to 9 reproduces typical field pH. Calibrate to your own towers.
×

1 to 20. About 5 to 9 fits most towers.

Multiplies every conservative ion.
×

1 to 15. Multiplies every conservative ion.

Acid FeedHold a target tower pH with acid. The model finds the alkalinity that pH allows and prices the difference.

The tower runs at its own pH.

Makeup Water AnalysisUnits as commonly reported. Sodium is filled by charge balance.
ppm as CaCO₃.
ppm
ppm as CaCO₃. If unknown: total hardness minus calcium hardness.
ppm
Total (M) alkalinity, ppm as CaCO₃.
ppm
ppm, or conductivity × 0.65. Used for the classic LSI and as a fallback ionic strength.
ppm
mg/L Cl. Optional, but improves the ionic strength.
mg/L
mg/L SO₄. Required for the gypsum check.
mg/L
mg/L SiO₂. Required for the silica checks.
mg/L
mg/L PO₄. Optional; enables the calcium phosphate check.
mg/L

Calcium, magnesium, and alkalinity as CaCO₃; the rest as the ion. Cycles come from the Cooling Tower Calculator.

Click on any stream to learn more.

Saturation at the Skin Temperature

All quantities are live and update with your inputs.

Will not persist. Predicted saturation this high will not persist: a real tower precipitates CaCO₃, consuming alkalinity and pulling pH down. Treat this as heavily scale forming, not as a literal concentration.

Operating Conditions
Cycles
4×
Bulk
85 °F
Skin
95 °F
pH
predicted
Acid
off
Makeup
no rate

Key Results

Primary outputs and operational context based on your inputs.

A screening level saturation model on published thermodynamic data and Davies activity corrections. Rigorous ion association software remains the reference standard for critical decisions; this tool tells you when you need it.

Tower pH The tower pH the indices are evaluated at, and the empirical rule of thumb beside it.

8.38 predicted

empirical rule of thumb 8.47

Saturation this high will not persist; the tower precipitates and pulls its own pH down.

Calcite Saturation index at the skin temperature, with the bulk beside it. A good inhibitor program controls calcite to about SI 1.5 to 2.

+1.80 SI at skin

+1.69 at bulk, scale forming

A good inhibitor program controls calcite to about SI 1.5 to 2; the color is the untreated tendency.

Gypsum Saturation index at the skin temperature. Sulfuric acid feeds it.

−1.05 SI at skin

under control, sulfate 240 mg/L

Sulfate driven; the acid choice matters.

Silica Degree of saturation of amorphous silica at the skin temperature, and the silica against the traditional 150 mg/L rule.

0.71 DS at skin

100 mg/L vs the 150 rule

Mg silicate product 16,000, under control.

Familiar Indices The classic indices at tower conditions, so the rigorous SI relates to what you know.

+1.75 LSI

RSI 4.87 · PSI 4.78

At tower conditions, so the rigorous SI relates to what you know.

Acid Price Delivered acid price per gallon.
$
per gal
Acid Feed Offno acid

Turn the acid feed on to price holding a target pH.