Description
Calculate a recorded pH value's signed reference difference.
Hydroponic records distinguish reservoir volumes, catch rates, media volume, nominal pump displacement and chemical reference labels. A top-up share can use final rather than initial volume, while a pH difference is not a chemical-dose calculation. Supplied parameters do not establish water quality, crop suitability or hydraulic performance.
Calculate a recorded pH value's signed reference difference.
When to use this tool
Use Hydroponic pH Reference Residual when you already have suppliedReferencePh, recordedPh and need to calculate a recorded pH value's signed reference difference.
How to use the tool and how it works
- Enter suppliedReferencePh, recordedPh. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read signedGap. Use the output convention below.
Return recordedPh-suppliedReferencePh.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| suppliedReferencePh | Supplied Reference Ph | Required. Finite number. |
| recordedPh | Recorded Ph | Required. Finite number. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| signedGap | recordedPh-suppliedReferencePh; a pH-scale difference, not a concentration ratio or dosing recommendation. | Required. Finite number. |
{
"input": {
"suppliedReferencePh": 12,
"recordedPh": 17
},
"output": {
"signedGap": 5
}
}Limitations and assumptions
- This subtracts pH readings only; it does not calculate hydrogen-ion concentration change, buffering, a chemical dose or a suitable pH target.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use calibrated water and flow observations, actual reservoir geometry and the complete intended chemical or hydraulic model. Preserve concentration, temperature-reference and time bases; local offsets and volume shares do not choose nutrient, pH or irrigation adjustments.
References
Similar or alternative tools
- Hydroponic Grow Media Water Holding Fraction
Calculate retained water as a fraction of supplied media bulk volume.
- Hydroponic Channel Slope Drop
Calculate a channel's signed vertical drop from run and supplied slope fraction.