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References & Online Calculators

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HydroTech Water Quality Calculators
All calculations run locally in your browser — no data is sent anywhere.

Temperature Accuracy

Inputs

Calculated Results

Oxygen Solubility

Inputs

Calculated Results

pH Buffer Temperature Correction

Each row has one input and one calculated result

Current temp for pH 4 buffer °C
pH 4 buffer @ current temp
Current temp for pH 7 buffer °C
pH 7 buffer @ current temp
Current temp for pH 10 buffer °C
pH 10 buffer @ current temp
Current temp for pH 6 buffer °C
pH 6 buffer @ current temp
Current temp for pH 6.86 buffer °C
pH 6.86 buffer @ current temp

pH Sensor Health

Inputs

Calculated Results

ORP Zobell Temperature Correction

Inputs

Calculated Results

Standard Methods relation used in the workbook: Eh, V = 0.229 - 0.0022 (T - 25).

SpConductivity to Salinity

Inputs

Calculated Results

Salinity conversion based on USGS Water-Supply Paper 2311.

Salinity to Chloride

Inputs

Calculated Results

S4000 NTU Formazin Dilution

Inputs

Calculated Results

NO3 Dilution

Inputs

Calculated Results

Workbook assumes starting with a 50 mg/L NO3 standard.

TDG Percent

Inputs

Calculated Results

Actual Barometric Pressure

Inputs

Calculated Results

Enter either mmHg or inHg. The other unit converts automatically. Formula: corrected pressure in mmHg minus 2.5 mmHg per 100 ft.

NO3-N to NO3

Inputs

Calculated Results

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