APERA INSTRUMENTS AI209 Value Series PH20 Waterproof pH Tester Kit
- ±0.1 pH accuracy, 0 to 14.0 pH range
- Up to 3 point auto calibration, 4.00 and 7.00 solutions included
- Auto temperature compensation, 0 to 50 °C
- IP67 water-resistant, 5 second response
- 4 AAA batteries included, up to 2000 hours
- 2 year warranty on the instrument, 6 months on the electrode
Last refreshed Oct 3, 2026 · Based on the Amazon listing and published specifications, not hands-on testing.
A pocket pH tester that handles its own setup, for water testing in hydroponics, pools or brewing. The probe cannot be assumed replaceable from this listing.
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ASIN: B01ENFOHN8Model: AI209Category: pH Meters
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Overview
Dipping the electrode into a sample and reading the digital display gives a pH value, with the meter flagging when the reading is stable. Automatic setup steps and a carrying case make it ready to use out of the box.
A general-purpose pocket meter for gardeners, pool owners, brewers and classrooms. The kit includes the calibration solutions, batteries and a lanyard, so it works out of the case. Probe replacement is not mentioned, so plan on the supplied electrode only.
Who it's for
Hobby growers, pool and spa owners, brewers and teachers who need routine checks. People needing tighter accuracy, or a probe they can swap, should look at a higher accuracy model.
Pros and cons
- Auto temperature compensation
- Batteries and solutions included
- Stable reading indicator
- Probe replacement not listed
- Hand wash only
- Electrode warranty shorter than instrument
Performance notes
The meter measures against the buffer solutions it is calibrated with, so fresh buffer solutions decide the real accuracy. Temperature compensation corrects the reading as the sample warms or cools. The stable-value indicator saves guessing when to read.
Where it stands among ph meters
- #4 most-searched brand and model of the 8 ph meters lines we track (by search demand, not sales).
From the specs of the 15 ph meters we list; not a test result.
Specifications
| Brand | Apera Instruments |
|---|---|
| Model | AI209 |
| Dimensions & fit | |
| Weight | 3.9 ounces |
| Length | 21.8 centimeters |
| Capacity & performance | |
| Measuring Range | 0 to 14.0 pH |
| Temperature range | 0 to 50 °C (ATC) |
| Power & efficiency | |
| Power Source | 4 AAA batteries (included), up to 2000 hours |
| Warranty & support | |
| Warranty Description | 2 years instrument, 6 months electrode |
| Other details | |
| Accuracy | ±0.1 pH |
| Display | Digital |
| Accuracy | CE, ISO 9001, RoHS |
| Calibration | Auto, up to 3 points |
| Water resistance | IP67 |
| Response Time | 5 seconds |
Closest rivals on specs
Frequently asked questions
Which calibration solutions does the Apera PH20 use?
The kit includes premixed 4.00 and 7.00 solutions, and the tester calibrates automatically on up to 3 points. It warns of incorrect buffer solutions and incorrect calibrations.
Is the Apera AI209 waterproof?
It is IP67 water-resistant, so it tolerates splashes and brief immersion, but the care line says hand wash only.
What comes in the Apera PH20 kit?
The pH tester, premixed calibration solutions, 4 AAA batteries, a lanyard and a portable carrying case.