The HORIBA LAQUAtwin conductivity pocket meter measures electrical conductivity — and on the EC-33, total dissolved solids — from a sample as small as 0.12 mL. The patented flat sensor sits on the sample surface instead of needing to be submerged, so you can test a few drops of soil extract, nutrient solution or process water without decanting into a beaker.

All three models are fully waterproof (IP67), calibrate at one button press, and use a user-replaceable sensor so a worn cell does not mean a new meter. Each ships with 1413 µS/cm and 12.88 mS/cm calibration solutions (14 mL each), batteries, dropper and storage case.

Choose your model

• LAQUAtwin EC-11 (part no. 3999960125) — conductivity only, 2-point calibration. Range 0–1999 µS/cm and 2.00–19.99 mS/cm.
• LAQUAtwin EC-22 (part no. 3999960126) — conductivity and temperature, 3-point calibration. Extends the range to 20.0–199.9 mS/cm for high-salinity samples.
• LAQUAtwin EC-33 (part no. 3999960127) — conductivity, TDS and temperature, 3-point calibration. Same wide EC range plus a direct TDS readout from 0 to 9900 ppm.

Conductivity or TDS?

Conductivity is the raw measurement; TDS is a calculated estimate of dissolved solids derived from it. If your records, permit or customer specification is written in ppm rather than µS/cm, choose the EC-33 so the meter does the conversion for you. If you only ever report in µS/cm or mS/cm, the EC-11 or EC-22 is all you need.

Applications

• Hydroponic and fertigation nutrient solution strength checks
• Soil salinity testing from a saturated paste or 1:5 extract
• Boiler, cooling tower and process water monitoring
• Reverse osmosis and deionized water quality verification
• Surface water, runoff and stormwater salinity spot checks
• Food and beverage QC on small or concentrated samples
• Aquaculture and greenhouse irrigation water monitoring
• Teaching laboratories and field training

Documentation

• LAQUAtwin pocket meter brochure and specifications (PDF)

Parts & accessories

Replacement S070 conductivity sensors, 1.41 mS/cm and 12.9 mS/cm standard solution sets, sampling sheets and the 6-meter carrying case are all stocked — see the Horiba Parts & Accessories collection.

Browse all HORIBA instruments.