pH Up Calculator for Hydroponics
KOH Dose for Nutrient Solutions
Example Hydroponic Water pH Adjustment Calculation
This example shows how the water pH adjustment calculator estimates the KOH required to raise the pH of a hydroponic nutrient solution.
Example input data
- Material: Liquid: Potassium hydroxide(KOH) 30%
- Reservoir volume: 100 L
- Current pH: 4.8
- Target pH: 5.3
- Water alkalinity as CaCO3: 10 ppm
Calculation result
Results show total KOH required and step-by-step dosing for precise pH adjustment.
Potassium Hydroxide (KOH) Requirement for pH Adjustment
This table summarizes the total potassium hydroxide (KOH) required to raise the pH of a nutrient solution in a hydroponic reservoir to the selected target pH, based on reservoir volume and buffering capacity.
| Parameter | Calculated value |
|---|---|
| Material | Liquid: Potassium hydroxide(KOH) |
| KOH volume | 0.6234 ml |
| Potassium(K) added | 1.72 ppm |
| Reservoir volume | 100 L |
• The calculated dose is an estimate based on buffering capacity and water chemistry.
• Always add KOH gradually, mix thoroughly, and re-measure pH.
• Potassium contribution should be considered in nutrient-balanced systems.
Step-by-step KOH Dosing Plan for pH Control
Gradual dosing is recommended. Splitting the total KOH dose into smaller steps helps prevent overshooting the target pH and provides better control in buffered nutrient solutions.
| Step | Δ pH | KOH | Added K (ppm) | Resulting pH |
|---|---|---|---|---|
| 1 | +0.17 | 0.1984 ml | 0.55 | 4.97 |
| 2 | +0.17 | 0.1984 ml | 0.55 | 5.13 |
| 3 | +0.17 | 0.2267 ml | 0.63 | 5.30 |
• Wait for full mixing before measuring pH after each step.
• Smaller doses are recommended for low-alkalinity or recirculating systems.
This example illustrates estimated KOH doses based on solution volume, initial pH, target pH, and alkalinity. Actual water response may vary, always verify pH after dosing.
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Frequently Asked Questions
- Use a pH up solution such as Potassium Hydroxide (KOH) to increase the pH of acidic hydroponic nutrient solutions. Enter your current pH, target pH, water volume, and alkalinity into the calculator to determine the correct KOH dose.
