Best pH Meter For Water: VIVOSUN pH Meter Digital PH Tester Pen for Water

If you need to test the pH level in a pool, spa or aquarium, our top pick would be the VIVOSUN tester pen. It is affordable and easy to use. Here’s more:

What We Liked

• Accurate (as long as you follow the instructions!).

• Easy to use.

• LCD backlit display.

• Includes packets to help you calibrate the pen.

• Includes long-lasting batteries.

What Needs Work

• Must be recalibrated after replacing batteries.

• Some users had issues trying to calibrate the pen. 

• Durability could be better. We see scattered reports that it pen stopped working (the LCD display gives out, for example) after a few months. If you need a heavy-duty or professional pH meter that is more durable, see our next recommendation.

Best Professional pH Meter: Aspera Instruments AI209 Value Series Waterproof pH Tester Kit

If you need to regularly use a pH meter and need a more robust solution for a tester kit, we’d recommend Aspera Instruments AI209 series waterproof pH tester kit. It has several advantages over basic testers, although it is more expensive. Here are the details:

What We Liked

• Fast and easy to use. • Accurate. • Can be automatically calibrated. Less expensive pH testers must be manually calibrated. • Loved the storage case.  • Smiley face indicates stable reading. • Auto shut-off. • Self-diagnosis function if something goes wrong during calibration.

What Needs Work

• Liquid on the tip confuses some folks. It’s supposed to be there on purpose–the lack of detail in the instructions can be a tad confusing. • Must be stored wet in a 4.0 pH solution. • Must separately buy calibration powder for 10 pH. That’s sub-optimal if you’re buying it to check for higher pH levels.

Best Soil pH Meter: Atree Soil pH Meter

Need to test soil to make sure your hydrangeas’ soil has the correct pH? We liked Atree’s soil pH meter best for gardeners.

Pro tip: for true blue flowers, hydrangeas must be in soil that is acidic (a pH of 5.5 to 6.5). Pink flowers must be in neutral or alkaline soils (6.5 pH or higher).

What We Liked

• No batteries needed.

• Easy to use.

• Easy to read.

• Excellent for hydrangeas.

• Toggle switch to test moisture or light.

What Needs Work

• Can’t use on dry soil. The soil must be wet for a reading. And it can take up to 10 minutes to get a reading, so you need a bit of patience!

Best Budget-Friendly: Sonkir Soil pH Meter

Yes, some soil meters can get rather pricey. We found that the Sonkir meter worked well in our testing—and the price is easy on the wallet. Here’s more:

What We Liked

• Easy to use.

• Measures soil moisture, pH value and sunlight intensity.

• Compact.

• No batteries.

What Needs Work

• Probes are a bit fragile. Don’t insert this into dry or hard soil, as it can damage the probes.

Why Trust Us

We’ve been rating and reviewing products for the home and families since 1994. We do hands-on testing—we buy the products with our own money and evaluate with an eye toward quality, ease of use and affordability.

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