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 3.0. The VIVOSUN AeroLab pH Pen leads on accuracy and features. The VIVOSUN AeroLab pH Pen costs $11.91 less ($65.99 vs $77.90).
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.
Milwaukee pH55 Pro
#11 in Pen testersFull review
A low-cost pen with a replaceable electrode, for pools, gardens and aquariums. The Apera PH60 is more accurate for a little more.
Amazon $77.90$77.90
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 replaceable probe, automatic temperature compensation, waterproof (IP65)).
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 | Milwaukee pH55 Pro |
|---|---|---|
| Overall rating | 3.7/5 | 3.0/5 |
| Accuracy 30% | 81 ±0.01 pH | 19 ±0.1 pH |
| Calibration 15% | 50 calibration points not published (neutral score used) | 50 2-point calibration |
| Features 20% | 80 replaceable probe, automatic temperature compensation, waterproof (IP67) | 70 replaceable probe, automatic temperature compensation, waterproof (IP65) |
| Extra readings 10% | 0 pH and temperature only | 0 pH and temperature only |
| Price 15% | 96 $65.99 | 89 $77.90 |
| Warranty 10% | 0 warranty not published, scored as none | 25 2-year meter warranty |
Specifications
| VIVOSUN AeroLab pH Pen | Milwaukee pH55 Pro | |
|---|---|---|
| pH measurement | ||
| Accuracy | ±0.01 pH | ±0.1 pH |
| Resolution | - | 0.1 pH |
| Range | - | -2 to 16 pH |
| Calibration | - | 2-point |
| Temperature compensation | Yes | Yes |
| Other readings | ||
| Conductivity (EC/TDS) | No | No |
| ORP | No | No |
| Salinity | No | No |
| Build | ||
| Replaceable probe | Yes | Yes |
| Waterproof rating | IP67 | IP65 |
| Battery life | - | 300 hours |
| Weight | - | 99 g |
| Meter warranty | - | 2 years |
| Probe warranty | - | 6 months |