The pH Buffer Powder Calibration Kit (3-Pack) provides a complete set of precision reference standards for calibrating digital pH pens, laboratory glass probes, and continuous water quality monitors. The kit includes three pre-measured powder sachets covering the full testing spectrum: pH 4.01 (acidic), pH 6.86 (neutral), and pH 9.18 (alkaline) at 25°C. Dissolving each packet into distilled water produces exactly 250ml of standard reference buffer solution, enabling full three-point calibration for maximum measurement linearity and accuracy.
Specifications
- Kit Contents: 3 sachets (pH 4.01, pH 6.86, and pH 9.18 buffer powders)
- Standard Calibration Temperature: 25°C
- Solution Yield: 250ml of standard buffer solution per packet (750ml total yield)
- Accuracy: ±0.01 pH at 25°C
- Sachet Dimensions: 60mm x 70mm x 3mm
- Net Weight: ~6g per packet
- Shelf Life (Sealed Powder): Up to 2 years (stored in a cool, dry place away from direct sunlight)
- Compatibility: Universal standard for all digital pH pens, benchtop laboratory meters, and industrial electrodes
Key Features
- Full 3-Point Calibration Capability: Covers acidic (4.01), neutral (6.86), and alkaline (9.18) points to accurately align both probe zero-offset and full-span electrode slope.
- Pre-Measured Accuracy: Eliminates the need for analytical laboratory balances—each sealed sachet dissolves cleanly into exactly 250ml of pure water.
- Extended Shelf Life: Dry powder formulation prevents degradation and atmospheric CO2 absorption, outlasting standard bottled liquid buffers.
- High Chemical Stability: Delivers repeatable, temperature-charted reference curves with ±0.01 pH precision.
Common Applications
- Hydroponics & Aquaponics: Routine calibration of nutrient reservoir monitors, dosers, and handheld testing pens.
- Aquariums & Aquaculture: Precise monitoring for planted freshwater tanks, brackish setups, and high-pH marine reef tanks.
- Water Treatment & RO Plants: Verifying drinking water purifiers, reverse osmosis systems, swimming pools, and industrial effluent neutralizing systems.
- Laboratories & Brewing: Food testing, craft beer mash tracking, soil pH sampling, and school chemistry education.
Preparation and Mixing Guide
- Prepare three clean containers (beakers, volumetric flasks, or clean glass jars) with a capacity greater than 250ml. Label them clearly: pH 4.01, pH 6.86, and pH 9.18.
- Pour the complete contents of each respective packet into its labelled container.
- Add exactly 250ml of distilled or deionized water to each container. Do not use tap water, bottled drinking water, or mineral water.
- Stir each solution thoroughly using a clean glass rod until the powder completely dissolves.
- The calibration reference solutions are ready for immediate use.
Calibration Best Practices
- Calibration Sequence: Always begin with the neutral solution (pH 6.86) to establish the electrode zero-offset. Follow with the acidic standard (pH 4.01) or alkaline standard (pH 9.18) depending on your expected testing range, or calibrate all three for full-range linearity.
- Rinse Between Solutions: Thoroughly rinse the pH probe tip with distilled water and gently blot it dry with a lint-free tissue between containers to prevent cross-contamination.
- Liquid Storage: Store prepared liquid solutions in airtight, tightly sealed glass or HDPE bottles in a cool, dark place (or refrigerator). Discard mixed solutions after 3 to 4 weeks, or immediately if discoloration or sediment appears.
- Temperature Compensation: Buffer pH shifts slightly with temperature. If your meter lacks Automatic Temperature Compensation (ATC), ensure the calibration solution temperature is as close to 25°C (77°F) as possible during adjustment.