Handheld pH/ORP/Conductivity/TDS/Salinity/Resistivity Multiparameter Meter Kit

What It Is

The Apera SX731 is a portable, handheld multiparameter water quality meter from Apera's SX700 series. In a single device — paired with three dedicated electrodes — it covers every water quality parameter a commercial cultivation operation routinely tracks: pH, ORP (redox potential), conductivity (EC), TDS, salinity, resistivity, and temperature. This is the complete AI467 kit, which means the meter ships with the 201T-S pH/ATC combination electrode, the 301Pt-S ORP combination electrode, the 2301T-S conductivity/temp electrode, pH buffer solutions (pH 4, 7, and 10), and a 1413 µS/cm conductivity standard — everything needed to calibrate and deploy right out of the case.

Apera designs the SX731 for lab-grade field measurement. That's not marketing language: the unit is rated IP57 (dust-tight; submersible to 1 meter), uses digital filter technology to improve response time and measurement stability in variable field conditions, and incorporates automatic temperature compensation (ATC, 0–50°C) across all relevant parameters. The result is a meter you can trust in a humid grow room, next to a reservoir, or outdoors at an environmental sampling point — not just on a clean bench.

Who This Meter Is Built For

For licensed cannabis and hemp cultivation facilities, the SX731 replaces the pile of single-parameter pocket testers that typically accumulate at a water station. Head growers and cultivation technicians who need to verify fertigation solution pH and EC before every irrigation event, confirm reservoir ORP as part of a sanitation or water-treatment protocol, or document run-off TDS and salinity for compliance or crop steering records will find this meter covers all of those checks from a single instrument.

It's equally applicable to water treatment intake points, environmental monitoring at licensed outdoor or greenhouse sites, and quality checks on water used in post-harvest processing. Operations running coco, deep-water culture, or recirculating hydro systems — where EC and pH swings between reservoirs and delivery points matter — benefit from the wide conductivity measurement range (0.00 µS/cm up to 200 mS/cm) that handles everything from RO/near-pure water to high-concentration nutrient solutions without switching instruments.

Key Features

Automatic electrode recognition is one of the SX731's most practical field features: connect any of the three included electrodes and the meter automatically switches to the correct parameter mode — no navigating menus to manually select pH vs. EC vs. ORP. Combined with 1-to-3-point automatic pH calibration (recognizing U.S., NIST, and China buffer series) and 1-point auto calibration for conductivity (covering a 0–200 mS/cm range from a single 1413 µS/cm standard), setup time in the field is minimal.

The 2301T-S conductivity electrode uses Apera's proprietary BPB (Brush-resistant Platinum Black) sensor technology, which delivers ±1% F.S. accuracy across the full 0–200,000 µS/cm measurement range and supports easy field cleaning. The 301Pt-S ORP electrode uses a platinum ring sensor with Ag/AgCl reference for stable potential and fast response — no ORP calibration required at the instrument level. The 201T-S pH/ATC electrode features a lithium glass membrane and ceramic single-junction diaphragm rated for general water solutions across the full 0–14 pH and 0–80°C temperature range.

Data logging stores and recalls up to 400 measurement sets, with self-diagnosis and auto power-off functions rounding out the intelligent-meter feature set. For operations that need to track water quality over time or produce records for state compliance or SOP audits, having 400 logged entries onboard — without needing a connected laptop — is meaningful.

How It Fits a Commercial Build

A single SX731 kit can cover an entire facility's daily water quality checks. In a multi-room or multi-tier cultivation layout, technicians carry the meter from room to room rather than running samples back to a fixed bench instrument. The rugged carrying case keeps all three electrodes, buffers, and standards organized and protected between uses, which reduces the likelihood of electrode damage or lost calibration solutions — a common cost center when equipment is shared across a team.

For operations expanding into new canopy, adding a second cultivation building, or converting a facility to recirculating fertigation, the SX731 is the portable reference instrument that validates the new system's water chemistry before crops go in. It also pairs naturally with inline or continuous monitoring controllers for cross-checking and calibration verification — where a continuous sensor drifts, this handheld provides the spot-check data to know when recalibration is needed. The 3-year manufacturer's warranty on the meter (6 months on electrodes) keeps the total cost of ownership predictable over a production cycle.