Multiparameter Sondes



6600 V2

6920 V2

600OMS V2

Legacy Sondes

All Legacy Sondes


CastAway CTD

Process Monitors

IQ SensorNet 2020 XT

IQ SensorNet 182

P 700 Orthophosphate

Aquaculture Systems

5200A Multiparameter

5400 MultiDO

5500 MultiDO Optical

AquaViewer App

Professional Series

Handheld Instruments

ProDSS Multiparameter

Pro Plus Multiparameter

ProODO Optical DO/OBOD

Pro30 Field Cond

Pro20 Lab/Field DO

Pro10 Field pH/ORP

Pro1020 Field DO/pH/ORP

Pro1030 Field pH/ORP/Cond

Pro2030 Field DO/Cond

Classic Handheld Series

556MPS Multiparameter

550A Dissolved Oxygen

63 pH/Conductivity

55 Dissolved Oxygen


900 Chlorine

910 COD

pHotoFlex Colorimeters

Laboratory Series


5000/5100 BOD/DO

3200 Conductivity

3100 Conductivity

MultiLab 4010-1

MultiLab 4010-2

MultiLab 4010-3

TruLab 1110

TruLab 1310 and 1310P

TruLab 1320 and 1320P


pH10A - pH Pen

pH100A - pH

ORP15A - ORP Pen

ODO200 - Optical DO

DO200A - DO

EC30A - Conductivity Pen

EC300A - Conductivity

9300/9500 Photometer

All YSI Accessories

Sensors, Cables, Calibration Solutions & more...

YSI Systems

Buoys & Floating Platforms

EcoMapper AUV

EcoNet Data-to-Web

Vertical Profiling

Towed Underwater Vehicles

Underway Sampling System

Other YSI Products

SonTek Acoustic Doppler Systems for water velocity

YSI Systems

DAA WaterLog

YSI Life Sciences


Blue-Green Algae

BOD (Biochemical Oxygen Demand)






Dissolved Oxygen



Oil / Hydrocarbon

ORP / Redox

Photosynthetic Active Radiation (PAR)





Specific Conductance


Total Dissolved Solids (TDS)


Colorimeter Parameters

Photometer Parameters





Drinking Water


Hydraulic Fracturing



Raw Water

Source Water

Storm Water

Surface Water


Watersheds / TMDL

Ask a Question

Events & Training

Find a Distributor

Product Service

Resource Library

Software Downloads

Welcome from the GM



Career Opportunities

Environmental Stewardship



Xylem Watermark

YSI - A Xylem Brand
Find YSI on Facebook Follow YSI on Twitter Watch YSI on YouTube
Login | Register


Wastewater sampling and monitoring for process productivity and laboratory testing. Handheld or unattended instruments are available for spot sampling dissolved oxygen, pH, ammonium, and ORP.

YSI IQ SensorNet Continuously Monitors Wastewater
YSI IQ SensorNet Continuously Monitors WastewaterYSI IQ SensorNet Continuously Monitors Wastewater YSI Professional Plus with Quatro Cable in WastewaterYSI Professional Plus with Quatro Cable in Wastewater YSI Professional Plus Measuring BOD in a Wastewater LaboratoryYSI Professional Plus Measuring BOD in a Wastewater Laboratory

Send me a Quote!

Find a Distributor

YSI has Authorized Distributors all over the globe. View a map and find your closest contact for YSI Wastewater products and accessories.

Find a Distributor

Get Support

Have a question about using your YSI equipment in Wastewater? Ask our application specialists!

Contact Technical Support

Product Service Centers

Want to return a product for service? Here you’ll find authorized service centers and instructions on how to send in your YSI Wastewater product.

Product Service

Wastewater management, whether municpal, industrial or from other sources, encompasses a broad range of efforts that promote effective and responsible water use, treatment, and disposal and encourage the protection and restoration of our nation's watersheds.

If wastewater was not properly treated it could easily cause negative impacts on the environment and human health.

Register to win a free optical dissolved oxygen / BOD system to help your facility properly manage its process and meet permit limits.

For laboratory testing of BOD the 5100 provides unmatched ease-of-use and accuracy. The Professional Plus, Pro20, ProODO optical DO and DO200 handheld instruments quickly become laboratory instruments with a simple change of probes providing for convenient field and lab use.

Reliable, unattended DO monitoring is easy with the ROX wiped dissolved oxygen sensor which addresses the challenges of waste water when used with the 6820 V2 sonde. For biological processes to work efficiently, continuous monitoring of the slightest changes in DO is critical and the ROX sensor is ideal for this application.

For multiparameter continuous water quality monitoring and control in your wastewater facility consider the YSI IQ SensorNet 2020 XT.  Measure multiple locations with up to 20 sensors.


EXO1 water quality sonde from YSI

EXO1 Water Quality Sonde

The EXO1 multiparameter water quality sonde collects data with up to four user-replaceable smart sensors and an integral pressure transducer for depth.


 EXO2 water quality sonde from YSI

EXO2 Water Quality Sonde

Collect data to 250 m with the advanced EXO2 sonde – six replaceable smart sensors and a central wiper to clean biofouling.


YSI 6820 V2 showing sensors, starting clockwise from top: ROX Optical Dissolved Oxygen, Turbidity, pH, ISE, and temperature/condutivity.

6820 V2

Compact Sonde for Field Sampling


The YSI 6820 V2 is a cost-effective data sonde for profiling and spot-checking water quality in rivers, lakes, wetlands, wells, estuaries, and coastal waters.


    YSI Professional Plus Shown with Single Parameter Cable and Probe Assembly

    Professional Plus

    Handheld Multiparameter Instrument


    The YSI Professional Plus handheld multiparameter meter provides extreme flexibility for the measurement of a variety of combinations for dissolved oxygen, conductivity, specific conductance, salinity, resistivity, total dissolved solids (TDS), pH, ORP, pH/ORP combination, ammonium (ammonia), nitrate, chloride and temperature. Also a very powerful lab instrument for BODs, pH and ORP.


    YSI ProODO Measuring Dissolved Oxygen in Aquaculture


    Handheld Optical Dissolved Oxygen Meter

    "We are very pleased with the convenience, usability, and ruggedness of the ProODO; and highly recommend it to anyone needing to monitor dissolved oxygen."


    The YSI ProODOTM handheld dissolved oxygen meter provides extreme durability for measuring DO with optical, luminescent based technology for field or lab.


    YSI Pro20 Lab or Field Dissolved Oxygen Meter


    Lab / Field Dissolved Oxygen


    The Pro20 provides everything you need in a handheld dissolved oxygen meter. Ruggedness, simplicity and reliability are the cornerstones of the instrument's design.


    YSI Pro1020 Dissolved Oxygen, pH or ORP Meter


    Field dissolved oxygen / pH / ORP

    The Pro1020 provides everything you need in a handheld meter that measures dissolved oxygen and temperature along with either pH or ORP (redox). Rugged, simple and reliable.

    Measure pH or ORP, dissolved oxygen, and temperature.


    YSI Pro2030 Field Dissolved Oxygen/Conductivity Meter


    Field Dissolved Oxygen / Conductivity

    "YSI did a great job on this design.  Our staff of about 20 people consists of old veterans to recent college grads, and not one so far has had a negative comment."

    The Pro2030 provides everything you need in a handheld dissolved oxygen meter that automatically compensates for changes in salinity values. Rugged, simple and reliable.

    Measure DO, salinity, conductivity, specific conductance, TDS, barometric pressure and temperature.


    YSI 556 Handheld Multiparameter Sampling


    Handheld Multiparameter Instrument


    Rugged, reliable and waterproof, the YSI 556 MPS (Multiprobe System) combines the versatility of an easy-to-use, easy-to-read handheld unit with all the functionality of a multiparameter system.


    YSI 5000/5100 Laboratory BOD and DO Meters

    5000 / 5100

    Laboratory Instruments for BOD Tests


    Both instruments feature: auto-calibration, large, graphic displays and low keypad profiles for maximum efficiency.


    YSI BOD Analyst Pro Screen Shot

    BOD Analyst Pro™

    Desktop Software

    Automatically calculate BOD/CBOD values with the BOD Analyst Pro desktop software.


    YSI 4010-1 Laboratory Instrument

    MultiLab 4010-1

    Laboratory Instrument for pH, ORP, conductivity and BOD in any combination

    Perform accurate lab pH, ORP, conductivity or BOD measurements with the YSI 4010-1.


    YSI MultiLab 4010-3 Laboratory Instrument

    MultiLab 4010-2 and 4010-3

    Laboratory Instruments for pH, ORP, conductivity, BOD and ISEs in any combination

    Perform accurate lab pH, ORP, conductivity, BOD or ISE measurements with the YSI 4010-2 or 4010-3 in any combination.


    YSI EcoSense pH10A pH Tester


    Pen-style pH Tester Instrument

    The pH10A is part of the EcoSense® family of products. It's the perfect instrument for economical spot sampling of pH and temperature in many applications including wastwater, surface water, aquaculture, hydroponics, pools, and education.


    YSI EcoSense DO200A Dissolved Oxygen Meter


    Dissolved Oxygen Meter


    The DO200A is part of the EcoSense® family of products. The DO200A dissolved oxygen instrument offers fast dissolved oxygen response times in wastewater, surface water, and aquaculture applications.


    YSI EcoSense 9300 Photometer

    9300 / 9500 Photometer

    Waterproof, rugged, easy to use photometers


    The YSI 9300 and YSI 9500 are economical photometers in small packages for any application. These portable photometers allow you to easily take readings directly in the field for 100+ parameters.


    Chlorine Testing - YSI 900 Chlorine Colorimeter

    900 Chlorine Colorimeter

    Waterproof, accurate, easy to use colorimeter

    The YSI 900 Free and Total chlorine colorimeter is ideal for any application. This portable instrument allows you to easily take readings directly in the field or lab.


    COD Colorimeter, YSI Model 910 COD Colorimeter

    910 COD Colorimeter

    Waterproof, accurate, easy to use colorimeter

    The YSI 910 COD colorimeter is ideal for any application. This portable instrument allows you to easily take readings for COD.


    Multiparameter Colorimeter - YSI pHotoFlex STD

    pHotoFlex Colorimeters

    The pHotoFlex line of colorimeters is the newest addition to YSI's full range of colorimeters. These rugged, waterproof, multiparameter colorimeters are ideal for laboratory and field testing.


    YSI IQ SensorNet 2020 XT Wastewater Monitoring System

    IQ SensorNet 2020 XT

    Improve Operational Efficiency with Continuous Data

    With an easily scalable solution, the 2020 XT allows for the connection of up to 20 sensors. This modular plug-and-play system allows you to monitor the water quality in your wastewater system continuously and accurately.

    "The simple cabling infrastructure - being able to run one cable that provides both power and data-transfer made so much sense."


    YSI IQ Sensor Net 182 XT Stacked on Modules

    IQ SensorNet 182 Models

    Improve Operational Efficiency with Continuous Data

    With an easily scalable solution the 182, 182 XT, and 182 XT-4 allow for the connection of 1-4 sensors depending on which terminal you choose. Add sensors at any time and at any location or change them out with ease. This completely modular plug-and-play system allows you to monitor the water quality in your wastewater or aquaculture system continuously and accurately.


    Catalogs & Brochures

    YSI Colorimetry Catalog

    BOD Testing

    IQ SensorNet Wastewater Process Monitoring & Control Catalog

    Water Quality Sampling for Field and Laboratory

    Wastewater - Water Quality Capabilities & Solutions

    IQ SensorNet Detailed Product Specifications Catalog (11 MB)

    Dissolved Oxygen Case Studies & Solutions

    Water Monitoring Solutions

    6-Series Multiparameter Water Quality Sondes

    Français - Sondes multiparamètres série 6 surveillance des eaux

    Deutsch - 6-Serie Multiparameter Wasserqualitäts-Messsonden

    Japanese - YSI 6シリーズ 多項目水質モニター

    Application Notes

    YSI IQ SensorNet Provides Reliable, Accurate Continuous Measurement for Troubleshooting Nitrification and Denitrification

    IQ SensorNet and SCADA Combined to Reduce Costs and Improve Effluent

    IQ SensorNet Continuous Process Monitoring of Ammonia and DO at WWTP

    IQ SensorNet Measures Turbidity and TSS in a Highly Productive Wastewater Plant

    Dairy Farms: YSI Instruments Map Volume of Wastewater Lagoons

    Small Team Saves Big Hassles with the Professional Plus Multiparameter Instrument

    ORP Management in Wastewater as an Indicator of Process Efficiency

    Improving Microbial Efficiency at Wastewater Treatment Plants with ROX™ Optical Dissolved Oxygen Sensor

    YSI Technology Used to Improve Wastewater Treatment Plant Efficiency and Effluent Quality

    Industrial Pretreatment Made More Efficient, Representative through the Use of YSI Technology

    Tech Notes

    Reducing Total Phosphorous in Water Resource Recovery Facilities

    BOD Analyst Pro Take 2 Leave 1 Rule

    How to Ensure Accurate and Successful BOD Measurements

    IQ SensorNet Understanding ISE Measurements in Wastewater Process Monitoring




    << Back to Applications page