Extech water quality meters are handheld, waterproof electrochemical instruments that measure the chemical and physical state of water directly in the field — chlorine, fluoride, turbidity, conductivity, total dissolved solids, salinity, dissolved oxygen, pH and oxidation-reduction potential. Instead of carrying samples back to a laboratory, the operator dips a sensor, reads a number, and acts on it while still standing at the tank, borehole, reservoir or discharge point.
Almost the entire range is built on Extech's ExStik platform: a pen-sized IP57 body with a screw-off, flat-surface electrode module. The flat electrode is the reason these meters survive site work — there is no fragile glass bulb to snap and no reference junction to clog, and the same sensor reads liquids, semi-solids and solids. When an electrode finally wears out, only the module is replaced, not the meter.
Ecotao stocks and supports the Extech water quality range across South Africa from Cape Town, with electrodes, reagent tablets, buffers and calibration standards held locally so a meter is not out of service waiting on an import.
How to choose an Extech water quality meter
Work from the decision you need to make, not from the parameter list. The question is almost always “what am I about to change, and what number tells me whether it worked?”
You are dosing a disinfectant
Chlorine residual tells you how much oxidant is left after demand has been satisfied; ORP tells you how effectively it is actually killing. Both matter, and they can disagree — high chlorine at low pH behaves very differently to high chlorine at pH 8.
Start with: CL200 → EX800 → EX900You are keeping something alive
Fish, shellfish and biofilter bacteria fail on oxygen first and everything else second. Measure dissolved oxygen at the depth stock actually occupies, not at the surface where the reading always looks healthy.
Start with: DO600 → DO600-K → DO610You are watching water get saltier or dirtier
Conductivity is the fastest single indicator of dissolved ionic load. It moves before anything else does when a borehole draws down, an RO membrane fouls, or an effluent stream changes character.
Start with: EC400 → EC500 → EC600You are controlling a chemical process
pH governs coagulation, precipitation, disinfection efficiency and corrosion. If you are adding lime, acid, coagulant or CO₂, pH is the control variable and everything else is a consequence of it.
Start with: PH100 → PH110 → EC600You have to prove it later
A number read off a screen and written on a clipboard is not evidence. If the reading may be questioned by a regulator, an auditor or a client, log it with a timestamp at the moment of measurement.
Start with: SDL100You need one kit for a whole site
Where several parameters are checked on the same round, a single multi-parameter meter beats three stick meters on both calibration time and the risk of an uncalibrated instrument being picked up by mistake.
Start with: EC600 or DO610Which Extech meter measures what
Every meter in the range against every parameter it reads. No single Extech handheld covers chlorine, dissolved oxygen and conductivity together — that combination needs a kit.
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| Model | Chlorine | Fluoride | pH | ORP | Conductivity | TDS | Salinity | Diss. oxygen | Temp | Logging |
|---|---|---|---|---|---|---|---|---|---|---|
| CL200 | ✓ | — | — | — | — | — | — | — | ✓ | 15 readings |
| EX800 | ✓ | — | ✓ | — | — | — | — | — | ✓ | 15 readings |
| EX900 | ✓ | — | ✓ | ✓ | — | — | — | — | ✓ | 15 readings |
| FL700 | — | ✓ | — | — | — | — | — | — | ✓ | 25 readings |
| EC400 / EC410 | — | — | — | — | ✓ | ✓ | ✓ | — | ✓ | 25 readings |
| EC500 / EC510 | — | — | ✓ | — | ✓ | ✓ | ✓ | — | ✓ | 25 readings |
| EC600 | — | — | ✓ | ✓ | ✓ | ✓ | ✓ | — | ✓ | 300 readings |
| DO600 / DO600-K | — | — | — | — | — | — | — | ✓ | ✓ | 25 readings |
| DO610 (kit) | — | — | ✓ | — | ✓ | ✓ | ✓ | ✓ | ✓ | 25 readings |
| PH100 / PH110 | — | — | ✓ | — | — | — | — | — | ✓ | 15 readings |
| PH220-C | — | — | ✓ | — | — | — | — | — | ✓ | Manual |
| RE300 | — | — | — | ✓ | — | — | — | — | ✓ | 15 readings |
| SDL100 | — | — | ✓ | ✓ | — | — | — | — | ✓ | SD card |
Chlorine, fluoride & turbidity meters
Disinfection control and drinking water compliance. These meters read the disinfectant and the additives directly, without the colour-matching step that makes comparator methods argue with themselves.
ExStik® Chlorine Meter
The CL200 reads total residual chlorine directly, from 0.01 to 10 ppm, using a solid-state electrode rather than a colour reaction. That distinction is the whole point of the instrument: colorimeters and comparators are thrown off by sample colour, turbidity, ambient light and dissolved organics, which is exactly the water most operators are testing. The CL200 is indifferent to all four. Drop a reagent tablet in the sample cup, dip the electrode, and read a number that will stand up in a dispute. Automatic electronic self-calibration means there is no calibration solution to keep in date for routine use.
- Chlorine
- Temperature
- Chlorine range0.01 – 10 ppm
- MethodDirect electrode
- Memory15 readings
- ProtectionIP57 waterproof
ExStik® 3-in-1 Chlorine, pH & Temperature Kit
Chlorine and pH are not independent variables — the same free chlorine residual is a far weaker disinfectant at pH 8 than at pH 7, because the hypochlorous acid fraction collapses as alkalinity rises. Measuring one without the other tells you half the story. The EX800 packages a CL200 meter with interchangeable chlorine and pH flat-surface electrodes, so both readings come from one meter body and one operator, on the same sample, seconds apart. Supplied with reagent tablets, buffer pouches, four sample cups, a weighted stand for hands-free measurement, batteries and a hard case.
- Chlorine
- pH
- Temperature
- ElectrodesChlorine + pH
- pH calibration1, 2 or 3 point
- DisplayDual LCD + bargraph
- Sample typesLiquid, semi-solid, solid
ExStik® 4-in-1 Chlorine, pH, ORP & Temperature Kit
The EX800 with an ORP electrode added, which closes the last gap in disinfection control. Chlorine residual says how much oxidant is present; ORP says how hard that oxidant is actually working against the organic and microbial load in front of it. Pool and process operators watch ORP because it responds to bather load and contamination faster than residual does, and because most automatic dosing controllers are ORP-driven — so a handheld ORP reading is how you audit whether the controller is telling the truth. Includes the CL200 meter, pH and ORP electrodes, 50 tests of reagent tablets, weighted stand and case.
- Chlorine
- pH
- ORP
- Temperature
- ElectrodesChlorine + pH + ORP
- Reagent supply50 tests included
- Self-calibrationChlorine and ORP
- Memory15 readings
Waterproof ExStik® Fluoride Meter
Fluoride has a narrow useful window — too little and the dental benefit disappears, too much and it becomes a health liability — which is why it is regulated by concentration rather than presence. The FL700 gives a direct ion-selective reading from 0.1 to 9.99 ppm in under a minute, in compliance with EPA Method 340.2, from a sample as small as 10 mL of water plus TISAB. It was the first fluoride meter to build automatic temperature compensation into the electrode itself, which is what makes a field reading comparable to a bench one. Two-point calibration and 25 labelled memory locations.
- Fluoride
- Temperature
- Range0.1 – 9.99 ppm (mg/L)
- MethodEPA 340.2 ISE
- Response timeUnder 1 minute
- Sample volume10 mL
Turbidity: Extech TB400 available on request
The Extech TB400 portable turbidity meter measures 0.01 to 1000 NTU to ISO 7027, complete with 0 NTU and 100 NTU standard bottles, cleaning solution and hard case. It is a current Extech product but is not yet listed as a card on this page. Contact us on +27 21 911 5835 or sales@ecotao.co.za for availability and lead time.
Conductivity, TDS & salinity meters
Conductivity is the fastest early-warning parameter in water treatment. It moves before turbidity, before pH and long before anyone notices a taste change.
ExStik® Conductivity / TDS / Salinity Meter
One patented multi-range cell, three autoranging spans from 0 to 19.99 mS/cm, which is wide enough to take the same meter from clean municipal tap water through borehole water to raw effluent without swapping sensors or thinking about range selection. Conductivity, TDS and salinity all derive from the same measurement, so the meter simply displays whichever unit the job calls for — and the conductivity-to-TDS ratio is adjustable from 0.4 to 1.0 so the TDS figure can be matched to the ionic character of your particular water rather than a generic factor.
- Conductivity
- TDS
- Salinity
- Temperature
- Conductivity0 – 19.99 mS/cm
- Accuracy±2% full scale
- TDS ratioAdjustable 0.4 – 1.0
- ProtectionIP57 waterproof
ExStik® Conductivity / TDS / Salinity Kit
The EC400 supplied with the things that make its readings defensible: 84, 1413 and 12880 µS/cm calibration standards in 30 mL bottles, spanning the meter's full working range. Calibrating a wide-range conductivity meter at a single mid-scale point and then trusting it at both extremes is a common and expensive mistake — three standards let you verify linearity where you actually work. Also includes a cast weighted base and sample cups for hands-free measurement, neck strap and carrying case.
- Conductivity
- TDS
- Salinity
- Temperature
- Standards84 / 1413 / 12880 µS/cm
- MeterEC400 included
- Hands-freeWeighted base + cups
- CaseCarrying case included
Waterproof ExStik® II pH / Conductivity Meter
The workhorse of the range. A single combination electrode — flat-surface pH plus autoranging conductivity cell — returns five parameters: conductivity, TDS, salinity, pH and temperature, in nine selectable units. One electrode means one thing to clean, one thing to store wet and one thing to replace, which matters more in daily use than any specification on the datasheet. The RENEW indicator tells you when electrode response has drifted past the point recalibration can fix, so meters do not quietly go out of tolerance between service intervals. An analogue bargraph shows which way a reading is trending while it stabilises.
- pH
- Conductivity
- TDS
- Salinity
- Temperature
- Units of measure9 selectable
- Memory25 labelled readings
- Salinity ratio0.5 fixed
- Electrode alertRENEW indicator
Waterproof ExStik® II pH / Conductivity Meter Kit
The EC500 with a full calibration set around it: three conductivity standards, three pH buffer pouches, rinse solution, sample cups, batteries and a carrying case. Buying the kit rather than the bare meter is the difference between a meter that gets calibrated and one that does not — if the buffers are already in the case, the calibration happens. This is the configuration Ecotao lists in the online store under SKU EX-EC510.
- pH
- Conductivity
- TDS
- Salinity
- Temperature
- Store SKUEX-EC510
- Standards3 conductivity + 3 pH
- Rinse solutionIncluded
- CaseCarrying case included
Waterproof Conductivity Kit — 7-in-1
Laboratory-grade performance in an IP57 field body: conductivity, TDS, salinity, resistivity, pH, mV and temperature. Two features separate it from the ExStik stick meters. First, non-linear temperature compensation below 10 µS/cm, which is what makes it usable on purified, RO permeate and boiler feed water where ordinary linear compensation produces nonsense. Second, resistivity as a native output, the unit high-purity water work is actually specified in. The 300-reading memory stores a series number, value and temperature per record, and one-button calibration recognises eight conductivity standards from the USA, European and Chinese series automatically.
- pH
- mV
- Conductivity
- TDS
- Salinity
- Resistivity
- Temperature
- Memory300 readings
- pH calibration1-button or 3-point
- Pure water ATCNon-linear <10 µS/cm
- DisplayBlue backlit dual LCD
Dissolved oxygen meters
The parameter with the shortest response time between a bad reading and dead stock. In aquaculture and biological treatment, oxygen is the constraint everything else operates inside.
Discontinued: Extech SDL150 Dissolved Oxygen Meter / Datalogger
The SDL150 has been discontinued by Extech and is no longer manufactured. There is no direct like-for-like replacement with SD-card logging for dissolved oxygen in the current range.
What to use instead: the DO600 covers the same measurement in a smaller waterproof body with altitude and salinity compensation; the DO600-K adds the 5 m cable and weighted guard for depth work the SDL150 needed a long probe for; and the DO610 kit adds pH and conductivity. If SD-card logging rather than dissolved oxygen is the real requirement, the SDL100 remains a current product for pH, ORP and temperature.
Ecotao can still supply replacement membranes and electrolyte for SDL150 units already in service. Extech's own compact alternative, the DO210, can also be sourced on request.
Waterproof ExStik® II Dissolved Oxygen Meter
Reads dissolved oxygen as concentration from 0 to 20.00 mg/L or saturation from 0 to 200%, and both compensations that make those numbers mean anything are adjustable on the meter. Altitude compensation runs to 20 000 feet in 1 000-foot steps, which covers everything from Cape Town harbour to the highest working site in the country. Salinity compensation runs 0 to 50 ppt for estuarine, brackish and marine water. Get either setting wrong and the meter will confidently report healthy oxygen in water that is actually suffocating stock — which is why these two controls matter more than the resolution figure.
- Dissolved oxygen
- % saturation
- Temperature
- Concentration0 – 20.00 mg/L
- Saturation0 – 200%
- Altitude comp.0 – 20 000 ft
- Salinity comp.0 – 50 ppt
ExStik® II Dissolved Oxygen Meter Kit
The DO600 plus the parts that let it measure where oxygen actually goes wrong: a 5 m extension cable and a weighted probe guard. Surface dissolved oxygen in a pond or a deep tank is almost always the best reading available and almost never the relevant one — stratification means the bottom metre can be anoxic while the surface reads comfortably saturated. Being able to drop a weighted probe to depth and profile down through the column is the difference between monitoring and guessing. Complete with spare membrane kit, batteries and hard carrying case.
- Dissolved oxygen
- % saturation
- Temperature
- Depth profiling
- Cable5 m extension
- Probe guardWeighted, included
- SparesDO603 membrane kit
- CaseHard carrying case
ExStik® II DO / pH / Conductivity Kit
Two meters, six parameters, one case: the DO600 dissolved oxygen meter paired with the EC500 pH and conductivity meter. This is the standard specification for recirculating aquaculture and aquaponics, because those three parameters move together and interpreting any one of them without the others is guesswork. Falling oxygen with rising conductivity and dropping pH is a biofilter under load; falling oxygen alone at stable pH is usually a blower or diffuser fault. Both meters are IP57 and weigh 110 g each, so the whole kit runs one-handed off a walkway.
- Dissolved oxygen
- pH
- Conductivity
- TDS
- Salinity
- Temperature
- MetersDO600 + EC500
- Parameters6 total
- ProtectionIP57 both meters
- Weight110 g per meter
pH & ORP (oxidation-reduction potential) meters
pH is the master variable in water chemistry — it sets coagulation efficiency, disinfection strength, metal solubility and corrosion rate. ORP measures the oxidising or reducing power that pH partly determines.
ExStik® pH Meter
The meter the rest of the ExStik line is built around. Its flat-surface electrode replaces the conventional glass bulb, and that single change removes the two failure modes that kill field pH meters: a bulb snapping against the side of a container, and a reference junction clogging in dirty water. It also lets the same electrode read semi-solids and solids — soil slurry, cheese, cement paste, carpet — not just liquids. Automatic temperature compensation, a stability indicator that tells you when the reading has settled, and a RENEW alert when the electrode is genuinely finished rather than merely due for recalibration.
- pH
- Temperature
- Range0 – 14 pH
- ElectrodeFlat surface, replaceable
- Sample typesLiquid, semi-solid, solid
- ProtectionIP57 waterproof
ExStik® Refillable pH Meter
Identical to the PH100 in every respect except the one that governs running cost: the reference electrode is refillable. On a sealed electrode, the reference solution slowly depletes and the whole module is discarded once it does — a fixed consumable cost regardless of how carefully the meter is treated. The PH110 lets you top up with KCl instead, restoring fresh reference solution and full accuracy, and removing shelf-life from the purchasing decision entirely. Worth specifying wherever a meter is used daily, or where a site holds spare electrodes that would otherwise expire on the shelf. Supplied with KCl, two reference junctions and removal tools.
- pH
- Temperature
- Range0 – 14 pH
- ElectrodeRefillable reference
- RefillKCl, 1.5 mL supplied
- Junctions2 spare included
Waterproof Palm pH Meter
Where the ExStik format runs out of reach, the PH220-C takes over. A waterproof palm-sized meter with a cabled BNC electrode, so the sensor goes into the vessel, borehole, channel or process line while the display stays dry in your hand. This is the right choice for anything you cannot dip a pen meter into: deep sumps, mixing tanks with agitators running, sample lines, and any situation where the operator needs to stand back from what is being measured. Uses the 6015WC waterproof electrode with built-in Pt-100 automatic temperature compensation.
- pH
- Temperature
- FormatPalm meter, cabled probe
- Electrode6015WC, 1 m cable
- ConnectorBNC
- Temp. comp.Built-in Pt-100
ExStik® ORP Meter
ORP answers a question chlorine residual cannot: how strongly is this water actually oxidising, right now. Because it responds to the net redox state rather than one chemical species, it tracks contamination load in real time and it is what most automatic dosing controllers use as their setpoint. A handheld RE300 is therefore both a process instrument and an audit tool — the way you confirm that a permanently installed ORP controller has not drifted. 1 mV resolution, automatic electronic self-calibration, 15-reading memory, and the same IP57 flat-surface ExStik platform as the pH meters.
- ORP / redox
- Temperature
- Resolution1 mV
- CalibrationAutomatic electronic
- Memory15 readings
- ProtectionIP57 waterproof
pH / ORP / Temperature Datalogger
When a reading has to survive being questioned months later, it needs a timestamp and a file. The SDL100 writes pH, ORP and temperature straight to an SD card in Excel format, date and time stamped, at intervals you set from one second to just under nine hours. No proprietary software, no driver, no transcription step — pull the card, open the file. That makes it the right instrument for compliance monitoring, effluent characterisation, commissioning trials and any overnight or unattended run. Three-point calibration for linearity across the range, 20 million readings on a 2 GB card, and 99 readings stored manually in the meter itself.
- pH
- ORP
- Temperature
- Datalogging
- pH accuracy±0.02 pH
- ORP range−1999 to 1999 mV
- LoggingSD card, Excel format
- Sample rate1 s to 8 h 59 min
Using these meters under South African conditions
Two things make water quality measurement in South Africa different from the assumptions built into most meter defaults: altitude, and the regulatory framework the readings feed into.
Altitude correction for dissolved oxygen
Oxygen solubility falls with barometric pressure, and South Africa has more of its population and industry above 1 200 m than almost any comparable country. A dissolved oxygen meter left on its sea-level default will over-report saturation on the Highveld, which is precisely where it will mask a genuine oxygen deficit. The DO600 and DO600-K carry adjustable altitude compensation in 1 000-foot steps up to 20 000 feet — set it once for the site and leave it. Approximate saturation values at 20 °C in fresh water:
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| Location | Approx. altitude | Altitude setting (ft) | Approx. DO at saturation, 20 °C |
|---|---|---|---|
| Cape Town / Durban / Gqeberha | 0 – 50 m | 0 | ~9.1 mg/L |
| Bloemfontein | ~1 400 m | 4 000 – 5 000 | ~7.7 mg/L |
| Pretoria | ~1 340 m | 4 000 | ~7.8 mg/L |
| Johannesburg | ~1 750 m | 5 000 – 6 000 | ~7.4 mg/L |
| Lesotho highlands sites | 2 000 m + | 7 000 + | ~7.1 mg/L |
Figures are indicative for planning and meter setup; always read the compensated value from the instrument rather than applying a table correction by hand.
SANS 241 and where handheld meters fit
SANS 241 sets South Africa's drinking water specification, and it distinguishes between determinands that need laboratory analysis and operational determinands that plant staff check on shift — free chlorine, pH, conductivity, total dissolved solids and turbidity among them. That operational layer is exactly what the Extech range is designed for: a CL200 or EX800 for residual chlorine at the point of dosing, an EC400 or EC500 for conductivity and TDS across the works, a PH100 for pH at every control step.
Formal compliance reporting to a water services authority normally requires analysis by a SANAS-accredited laboratory, so the workable pattern is continuous in-house monitoring with handhelds, backed by periodic confirmatory samples sent out. Handheld readings that are logged rather than written down — the SDL100 case — also make the operational record far easier to defend during a Blue Drop or Green Drop assessment.
Water reuse, boreholes and load-shedding
Two South African realities drive most of the conductivity meters Ecotao sells. The first is groundwater: as boreholes are drawn harder, conductivity climbs, and it climbs measurably before anyone tastes a difference — a weekly EC400 reading on a borehole is the cheapest early warning of over-abstraction available. The second is intermittent power. Every unplanned stop in an aeration or dosing system leaves a signature in dissolved oxygen and ORP, and a DO600 reading taken shortly after power returns tells you whether the biology in a treatment train or a fish tank actually survived the outage, while there is still time to intervene.
Frequently asked questions
The questions we are asked most often about specifying, calibrating and maintaining Extech water quality meters.
What is the difference between an ExStik and an ExStik II meter?
ExStik is Extech's original waterproof pen-format platform with a screw-off flat-surface electrode module, used by the PH100, PH110, CL200, RE300, FL700 and EC400. ExStik II is the later generation that adds multi-parameter sensing to the same body, so a single electrode reports several values at once — the EC500 measures conductivity, TDS, salinity, pH and temperature from one combination electrode, and the DO600 adds altitude and salinity compensation for dissolved oxygen. Both generations share the same IP57 housing, the same replacement-electrode approach and the same neck strap, so an operator trained on one is immediately productive on the other.
Which Extech meter should I buy for a fish farm or aquaculture system?
Dissolved oxygen is the parameter that kills stock fastest, so start with a DO600 or, for tanks and dams deeper than about a metre, the DO600-K with its 5 m weighted cable. Recirculating systems also need pH and conductivity tracked as biofilter load changes, which makes the DO610 kit the usual choice because it pairs the DO600 with the EC500 in one case. If the water is disinfected between batches, add an RE300 ORP meter or step up to the EX900 kit so chlorine residual and oxidising potential can both be checked before restocking.
Do I need to correct dissolved oxygen readings for altitude in South Africa?
Yes, and it matters more here than in most markets. Oxygen solubility falls with barometric pressure, so at Johannesburg's roughly 1 750 m the saturation concentration is around 80% of the sea-level value. A meter left on a sea-level setting will read high and can mask genuine oxygen stress. The DO600 and DO600-K carry adjustable altitude compensation in 1 000-foot steps up to 20 000 feet, which covers every inhabited altitude in the country, plus salinity compensation from 0 to 50 ppt for estuarine and marine work at the coast.
Why does an Extech chlorine meter give different results to a DPD colour comparator?
A DPD comparator infers chlorine from a colour change, so anything that alters the appearance of the sample distorts the result — coloured or turbid raw water, strong ambient light and dissolved organics all shift the reading, and the final judgement is a human colour match. The CL200 used in the EX800 and EX900 kits reads total residual chlorine electrochemically from 0.01 to 10 ppm, so the measurement is a direct numeric value unaffected by sample colour, turbidity or light. Expect the meter to disagree with a comparator on dirty water, and to be the more defensible number.
Is the Extech SDL150 dissolved oxygen datalogger still available?
No. Extech has discontinued the SDL150 and there is no direct like-for-like replacement in the current range. For most users the DO600 covers the same measurement in a smaller waterproof body, and the DO600-K adds the 5 m cable needed for depth work. If SD-card logging is the specific requirement rather than the dissolved oxygen measurement itself, the SDL100 remains current for pH, ORP and temperature. Ecotao can still supply membranes and electrolyte for SDL150 units already in service.
How often should Extech ExStik electrodes be calibrated and replaced?
Calibrate pH before each measuring session in regulated work, or weekly for routine monitoring, using fresh 4, 7 and 10 pH buffers. Conductivity holds calibration longer and typically needs a single-point check monthly against a 1413 µS/cm standard. ExStik pH and conductivity meters display a RENEW indicator when electrode response has degraded beyond correction — that is the point to fit a replacement module rather than recalibrate again. In practice a flat-surface pH electrode used daily in wastewater lasts six to twelve months, and considerably longer in clean water.
Which meter covers the most parameters in a single instrument?
The EC600 is the broadest single meter in the range, reading conductivity, TDS, salinity, resistivity, pH, mV and temperature with a 300-reading memory and non-linear temperature compensation for purified water below 10 µS/cm. It does not measure dissolved oxygen or chlorine. If dissolved oxygen must also be covered, the DO610 kit reaches six parameters across two meters, and the EX900 kit adds chlorine and ORP. There is no Extech handheld that covers chlorine, dissolved oxygen and conductivity in one body.
Are Extech water quality meters suitable for SANS 241 drinking water compliance testing?
They are well suited to operational and screening measurement against SANS 241 limits, which is where most testing volume sits. Free chlorine, pH, conductivity, TDS and turbidity are all operational determinands that plant staff check on shift, and the CL200, PH100, EC400 and EC500 give traceable numbers for that purpose. Formal compliance reporting to a regulator normally requires analysis by a SANAS-accredited laboratory, so the usual pattern is continuous in-house monitoring with Extech handhelds and periodic confirmatory samples sent to an accredited lab.
Not sure which meter fits your application?
Tell us what water you are testing, what decision the reading has to support, and where the site is. We will specify the right meter, the electrodes and standards it needs, and the consumables to keep on the shelf — and say so plainly if a different brand in our range suits you better.
39 Olienhout Avenue, Plattekloof 3, Cape Town, Western Cape