Seven parameters. One portable meter. EPA Method 340.2 fluoride compliance built in.
The Apera WS200 (AI4721) is a rugged 7-in-1 portable meter that measures fluoride, pH, conductivity, TDS, salinity, resistivity, and temperature from a single handheld unit. Purpose-built for operators who need traceable, lab-grade water quality data in the facility or in the field — without carrying multiple instruments.
The Apera WS200 is a professional-grade portable multiparameter meter designed for accurate, field-ready water analysis. Model AI4721 ships as a complete kit: the W2100 meter body, the patented F501 3-in-1 ATC fluoride ion probe (ion electrode + reference electrode + temperature electrode in one housing), a 201T-S ATC combination pH electrode, a 2301T-S ATC conductivity probe, fluoride calibration solutions (0.19 mg/L and 19.00 mg/L), pH calibration solutions (pH 4.00, 7.00, and 10.01), a 1413 µS/cm conductivity calibration solution, backup batteries, a screwdriver, an instruction manual, and a carry case. Everything required to put the meter into service is in the box.
The meter is compliant with EPA Method 340.2 for fluoride ion measurement — a requirement for operations subject to municipal water quality reporting or state environmental compliance programs. All three probes feature automatic temperature compensation (ATC), so readings stay accurate across varying source-water temperatures without manual correction.
Licensed cannabis and hemp cultivation operations run on water quality. EC and pH management are non-negotiable for nutrient delivery accuracy in any medium — coco, rockwool, DWC, NFT, or soil. The WS200 consolidates what would otherwise be three separate instruments (a pH meter, an EC/TDS/salinity meter, and a fluoride ISE meter) into one portable kit that moves between fertigation stations, reservoir check points, and intake water testing without re-setup.
The fluoride channel is particularly relevant for operations on municipal water supplies where fluoride levels can interact with certain nutrient chemistries and where regulatory water-quality records may be required. The 0.02–1900 ppm fluoride range and EPA Method 340.2 compliance make this a defensible instrument for those records. TDS and salinity channels serve aquaponic and recirculating system operators who need full ionic load accounting beyond EC alone. The IP57 water-resistance rating means the meter holds up to the wet, humid environments typical of commercial grow rooms.
The patented F501 3-in-1 fluoride probe is the core differentiator of this kit. Unlike traditional ISE setups that require sample stirring or reagent addition before every measurement, the F501 reads directly from the sample — the same workflow as a standard pH test. The probe requires only a 10-minute activation prior to the first use of a session. Calibration is 2-point automatic using the included standards (0.19 mg/L and 19.0 mg/L). Fluoride units are user-switchable between mg/L, ppm, ppt, and pF.
pH calibration runs to 3 points automatically (4.00, 7.00, 10.01), and conductivity calibration is 1-point. The meter auto-recognizes up to 8 conductivity standard solutions across USA/Europe and China series. The large backlit display stores 800 measurement sets including measured value, temperature, and units. Additional intelligent functions include auto power-off, backlight adjustment, and self-diagnosis. ORP measurement is supported with a separately sold ORP probe.
For a multi-room or multi-site operation, having one standardized meter kit at each intake or fertigation point — rather than a patchwork of pocket testers — keeps QC data consistent and auditable. The 800-reading onboard memory means a head grower or cultivation director can capture an entire day's data set across multiple reservoirs and review or export it later rather than transcribing readings in real time.
The carry case and IP57 rating make this practical for operations where the meter travels between a water treatment room, a propagation bay, and a flower room in a single shift. Because the fluoride, pH, and conductivity probes each connect independently to the W2100 meter body, individual probe replacement doesn't require replacing the full instrument — keeping long-run calibration costs manageable. The 2-year instrument warranty and 6-month probe warranty from Apera cover the full kit from delivery.
| Model | WS200 |
| SKU | AI4721 |
| Parameters | Fluoride, pH, Conductivity (EC), TDS, Salinity, Resistivity, Temperature (ORP with optional probe) |
| Fluoride Range | 0.02 to 1900 ppm |
| Fluoride Accuracy | ±0.02 ppm or ±5% of reading (whichever is greater) |
| Fluoride Calibration | 2-point automatic (0.19 mg/L, 19.0 mg/L); EPA Method 340.2 compliant |
| pH Range | 0 to 19.99 pH |
| pH Accuracy | ±0.01 pH |
| pH Calibration | 3-point automatic (pH 4.00, 7.00, 10.01) |
| Conductivity Range | 0 to 200 mS/cm |
| Conductivity Accuracy | ±1% full scale |
| Data Storage | 800 measurement sets |
Yes. The AI4721 kit includes the W2100 meter, the F501 3-in-1 fluoride ion probe, the 201T-S pH electrode, the 2301T-S conductivity probe, fluoride calibration solutions at both calibration points (0.19 mg/L and 19.00 mg/L), pH buffers at three points (4.00, 7.00, 10.01), a conductivity calibration solution, backup batteries, and a carry case. The only thing needed to add ORP measurement capability is an optional ORP probe, sold separately.
Yes. The WS200 with the F501 fluoride probe is compliant with EPA Method 340.2 for direct fluoride ion measurement. This makes it suitable for applications where regulatory documentation of source or process water fluoride levels is required.
No. The patented F501 3-in-1 electrode measures fluoride ion concentration directly, the same way a standard pH electrode reads pH — no sample stirring and no reagent addition required. A 10-minute probe activation prior to the first test of a session is all that's needed.
Yes. The fluoride probe (F501), the pH electrode (201T-S), and the conductivity probe (2301T-S) each connect independently to the W2100 meter body and are available as individual replacement parts. You do not need to replace the full kit if one probe reaches end of service life.
The WS200 is rated IP57 for water and dust resistance and ships with a silicone-protected housing and carry case, making it suitable for both controlled lab environments and field or facility use. The portable form factor and onboard 800-point data storage are specifically designed for mobile, multi-point testing across a production facility.
Get operator-direct pricing and availability. We supply licensed commercial cultivators nationwide.
Request a Quote