Apera Instruments
Fluid Precision Since 1991

Gro’Star® Series & Beyond

35+ years of electrochemical sensor expertise. ISO 9001 certified, in-house manufacturing across 60+ countries. From pocket pH pens to benchtop multiparameter meters — precision measurement for every scale of cultivation.

IP67 WaterproofReplaceable ProbesTruRead™ Mode
Apera GS4 waterproof pH/EC combo pen tester
Apera Gro'Star Series complete lineup - GS1, GS2, GS3, GS4

The Gro’Star Series is Apera’s dedicated horticulture line — Gen II lab-grade pen testers purpose-built for growers. Every model features IP67 waterproof construction (floatable), 3-color backlit LCD for dark grow rooms, replaceable probes, and TruRead™ mode that averages readings across multiple sample points for true accuracy.

Gro’Star Product Lineup

Apera GS1 — pH Pen
GS1 — pH Pen
pH 0–14 · ±0.1
Apera GS2 — Soil pH Pen
GS2 — Soil pH Pen
Direct soil / coco / rockwool
Apera GS3 — EC/ppm Pen
GS3 — EC/ppm Pen
0–10 EC · 500/700 ppm
Apera GS4 — 5-in-1 Combo
GS4 — 5-in-1 Combo
pH+EC+ppm+Temp

Why Apera

IP67 Waterproof & Floatable

Drop it in the reservoir — it floats. Fully submersible and sealed for the harshest grow room conditions. No more replacing meters after accidental dunks.

TruRead™ Mode

Takes measurements across multiple points, then automatically calculates and displays average, minimum, and maximum values. True accuracy, not a single-point guess.

Replaceable Probes

Never throw away the whole pen. All Gro’Star models use replaceable probes that snap in. The instrument lasts for years; just replace the sensor when needed.

3-Color Backlit LCD

White for measurement, green for calibration, red for errors. Instantly readable in dark grow rooms. No squinting at screens under HPS or green light.

35+ Years Manufacturing

ISO 9001 certified facility in Columbus, Ohio. In-house sensor manufacturing across 60+ countries. 2-year instrument warranty, 1-year probe warranty on Gro’Star.

Dual ppm Scales

Both 500-scale and 700-scale ppm modes built in. Compatible with any nutrient brand’s feed chart — no conversion math needed.

35+
Years Experience
IP67
Waterproof
ISO
9001 Certified
60+
Countries
2yr
Warranty
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