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APERA INSTRUMENTS AI209-T Value Series PH20 pH Tester Combo Kit, Including the Maintenance Set, and a CalPod Solution Holder for Easy Calibration

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Availability: In Stock.
Fulfilled by Amazon

Arrives Tuesday, Aug 25
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Style: Combo Kit


Features

  • The top-rated pH tester now comes with a complete CALIBRATION and PROBE CARE Combo Kit, ensuring reliable test performance
  • Comes with a probe cleaning brush for easy removal of contaminants on probes, maximizing probe's life-span
  • Comes with Apera's unique CalBox, heping you organize all the solutions and save cost on buffers by at least 50%
  • Apera quality pH sensor with low impedance, greatly improving response speed and shorteninb stablizing process
  • Easy auto. calibration with buffer recognition; auto. temp. compensation (ATC) ensures accuracy in various temperatures (32 to 122 F)

Description

"The top-rated pH tester on Amazon now comes with a complete calibration and probe care combo kit, including 3 bottles of 8oz pH calibration solutions (pH 7, 4 & 10), one 4oz 3M KCL storage solution, a probe cleaning brush, and Apera's unique CallBox for organizing all the solutions and efficient use of buffer solutions (help you save the cost on buffers by at least 50%). Performing pH calibration in fresh and clean calibration solutions regularly is critical to the reliable performance of pH meters. As a rule of thumb, we recommend calibrating your pH meter at least once a week. And each batch of calibration solutions should be replaced after 10-15 times of calibration. With Apera's Callbox and 8oz calibration solutions, users can perform up to 150 times of calibration. The probe cleaning brush that comes with the kit can help you easily remove contaminants on the glass bulb sensor without any damage, maximizing the life span of your pH probe.The PH20 Value pH Tester is designed for all kinds of regular water solutions pH test, including hydroponics, pools and spas, water treatment, aquariums, aquaculture, beer brewing, winemaking, cooling towers, etc. Up to 3 points of auto. calibration and 0 to 50˚C Auto temperature compensation (ATC), ±0.1 pH Accuracy with 0 to 14.0 pH measuring range; auto. recognition and auto. indication of stable readings saves you the trouble of guessing when to manually hold measurement. With a clear large screen, it supports dual display of Temp./pH value and indicators of completed calibrations (where L/M/H indicate 3 points of calibrations) and stable readings (with a smiley face). Smart self-diagnosis, warning of out-of-range measurement and incorrect calibrations. IP67 waterproof and dustproof. Up to 2000 hours' continuous operation powered by AAA batteries (with low power warning and Auto power off in 8 min if no operation). 6-Month on the the probe. "

Product Dimensions: ‎7 x 1.6 x 1.2 inches


Item Weight: ‎3.3 pounds


Manufacturer: ‎Apera Instruments


Item model number: ‎AI209-T


Batteries: ‎4 AAA batteries required. (included)


Date First Available: ‎December 7, 2017


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Tuesday, Aug 25

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Great PH meter for liquids - read if you formulate creams
Style: Combo Kit
I use this meter for cosmetic formulation. It’s accurate for water-based solutions, but if testing viscous creams, conditioners, especially anything cationic (formulas with BTMS, CETAC, etc.): the meter will often freeze at pH 3.9 no matter what you do. This happens because the probe is being coated and losing contact with the sample. Solution: Always test a 1 : 10 dilution with distilled water. After use, rinse with water and soak 10 min in 1 : 1 vinegar + water and store in KCl solution. Calibrate once a week. Once you follow the steps, readings should be accurate. It’s a good tool, but requires some maintenance for creamy products. Without proper cleaning, it looks like every batch is pH 3.9 which might waste a lot of your time and calibration buffer solution troubleshooting. ... show more
Reviewed in the United States on October 18, 2025 by mjaa

  • Aquarium and House Plant -- Water Testing
Style: Combo Kit
The quality of this product is significantly better than the $10 dollar brands. Obtains stable final reading faster and maintains calibration longer. The entire device is water proof. I have accidentally dropped my various meters multiple times fully submerged in water. Finally, the included directions are more informative than the two other cheap brands that I purchased. ... show more
Reviewed in the United States on December 22, 2025 by Paul

  • Accurate and easy to use
Style: Combo Kit
The unit functions great and is accurate. I was disappointed when it stopped calibrating one day, so I read the troubleshooting steps, one of which said to soak it in the 3M KCL storage/soaking solution. I was previously storing it in reverse osmosis water and didn't even realize it came with some KCL storage/soaking solution until I looked through my things. So I soaked in the KCL for a day, and viola, that fixed the issue. ... show more
Reviewed in the United States on September 5, 2024 by Walter

  • Durable product
Style: Combo Kit
Great product with the bottle started to leak while being stored
Reviewed in the United States on July 16, 2026 by Michael

  • Spend the $$$ once and be done with it -
Style: Combo Kit
I have bought several of the cheaper PH pens and after several months of use, it has to be recalibrated and that process is not easy. The ph readings are inaccurate and eventually I get another cheap one. Well, over the weekend, I needed to check the ph of one of my aquariums. I pulled out the latest ph pen I had, though it was working properly. It was not working. I went ahead and ordered this Apera PH tester. What a joy to use and calibrate. I should have bought in the beginning and I would not have to go through frustrating situations when I needed to get the accurate ph reading. Well worth the cost. ... show more
Reviewed in the United States on July 23, 2024 by gfrontosa

  • This pH tester is quality and reasonable price.
Style: Combo Kit
I brought this in combo kit for food and wine pH test. It reasonable price and accurate as good as my other top name brand I have. Yes I will buy another one again in future from this company.
Reviewed in the United States on June 26, 2025 by A-N

  • works
Style: Combo Kit
these work well & will outlive 10 or more of the cheapo type. well worth the money.
Reviewed in the United States on November 27, 2025 by john kohler

  • Easy to use!!
Style: Combo Kit
First time user... Love this kit!! Highly recommend!! Fast, simple & accurate 3 points calibration. Excellent video links on the Amazon site & printed direction in the case to help your step right through the he process of calibration and use. 😎
Reviewed in the United States on April 30, 2025 by BikerHippie71

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