VIVOSUN AeroLab pH Pen
#4 in Pen testersFull review
A low-cost grower’s pen with a replaceable probe. Its maker publishes little beyond the accuracy claim.
Amazon $65.99$65.99
The VIVOSUN AeroLab pH Pen is the better ph meter overall, rated 3.7 to 3.1. The VIVOSUN AeroLab pH Pen leads on accuracy and features. The Apera PH20 costs $9.34 less ($56.65 vs $65.99).
Prices were last checked November 9, 2026. Product prices and availability are accurate as of that date and are subject to change; the price and availability shown on Amazon or the retailer's site at the time of purchase apply. As an Amazon Associate we earn from qualifying purchases.
Apera PH20
#9 in Pen testersFull review
A cheap, waterproof pen for pools, aquariums and drinking water. Pick it when 0.1 pH is close enough.
Amazon $56.65$56.65
Which should you buy?
- Choose the VIVOSUN AeroLab pH Pen for accuracy (±0.01 pH vs ±0.1 pH) and features (replaceable probe, automatic temperature compensation, waterproof (IP67) vs automatic temperature compensation, waterproof (IP67)).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every pen testers ph meter; a clear win is highlighted. How we rank explains each one.
| Factor weight | VIVOSUN AeroLab pH Pen | Apera PH20 |
|---|---|---|
| Overall rating | 3.7/5 | 3.1/5 |
| Accuracy 30% | 81 ±0.01 pH | 19 ±0.1 pH |
| Calibration 15% | 50 calibration points not published (neutral score used) | 85 3-point calibration |
| Features 20% | 80 replaceable probe, automatic temperature compensation, waterproof (IP67) | 50 automatic temperature compensation, waterproof (IP67) |
| Extra readings 10% | 0 pH and temperature only | 0 pH and temperature only |
| Price 15% | 96 $65.99 | 100 $56.65 |
| Warranty 10% | 0 warranty not published, scored as none | 25 2-year meter warranty |
Specifications
| VIVOSUN AeroLab pH Pen | Apera PH20 | |
|---|---|---|
| pH measurement | ||
| Accuracy | ±0.01 pH | ±0.1 pH |
| Resolution | - | 0.1 pH |
| Range | - | 0 to 14 pH |
| Calibration | - | 3-point |
| Temperature compensation | Yes | Yes |
| Other readings | ||
| Conductivity (EC/TDS) | No | No |
| ORP | No | No |
| Salinity | No | No |
| Build | ||
| Replaceable probe | Yes | No |
| Waterproof rating | IP67 | IP67 |
| Battery life | - | 2,000 hours |
| Weight | - | 107 g |
| Meter warranty | - | 2 years |
| Probe warranty | - | 6 months |