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Water Quality Monitor for Conductivity, Temperature, Depth, Dissolved Oxygen, Turbidity, Chlorophyll, CDOM

Water Quality Monitor

The Sea-Bird Coastal WQM/WQM X with technology by Sea-Bird Electronics and WET Labs combines state of the art fluorometers with cutting edge conductivity, temperature, depth and dissolved oxygen sensors.

Ideally suited for unattended monitoring the WQM and WQM X employ active flow control, passive flow prevention, light-blocking, active biocide injection and passive inhibitors to effectively and safely combat internal and external fouling. With fouling minimized, the superior inherent stability of the WQM/WQM X sensors translate directly to superior long-term data quality.

The cost of monitoring is tied to the instrument life cycle and real value is ultimately provided through quality data, day after day, month after month, year after year. The WQM/WQM X provides quality data while dramatically reducing the need for field and factory service.



Range0-9 S/m
Accuracy0.003 mS/cm
Resolution0.00005 S/m


Range0-100 or -200 m
Accuracy 0.1% Full Scale
Resolution0.002% Full Scale


Chlorophyll EX/EM 470/695 nm
Accuracyd0.2% FS µg/I


0 - 50 µg/I

CDOM EX/EM 370/460 nm
Sensitivity0.09 ppb
Range0 - 500 ppb


ConnectorMCBH-6-MP, MCBH-4-FS
Input9-16 VDC

Sample rate

1 Hz
Current draw 

<100 mA Sampling

350 mA Peak

< 50 µA Sleep


Rangea -5-35 deg C
Accuracyb0.002 deg C
Resolution0.001 deg C


Range120% of saturation (200% upon request)
Accuracy2% of saturation
Resolution0.035% of saturation (0.003 ml/l at 0 C, 35 PSU)


Range0-25 NTU
Accuracy0.1% FS NTU

0.04% FS NTU

Wavelength700 nm


Depth200 m
Pressure housingAcetal copolymer, ABS, PVC, titanium, copper
Dimensions65.4 cm long x 18.5 cm max OD
Weight in air5.4 kg
Weight in water1.8 kg

a. Oxygen range is relative to surface saturation.

b. +/- 0.2 mg/l or 2% of reading, whichever is greater.
c. Available measurement ranges:
  • 0–30 μg Chl/l, 0–10 NTU
  • 0–50 μg Chl/l, 0–25 NTU
  • 0–50 μg Chl/l, 0–100 NTU
  • 0–75 μg Chl/l, 0–200 NTU
  • 0–125 μg Chl/l, 0–350 NTU
  • 0–250 μg Chl/l, 0–1000 NTU
d. Chlorophyll fluorescence is created by living organisms and is subject to taxonomical and physiological changes. Field calibration is highly recommended. See user’s guide for standard protocols.
e. Depth rating is the lesser of 200 m or the pressure sensor rating.
Specifications are subject to change without notice.
Product Brochure

WQM X Brochure

Thursday, October 31, 2013
Application Article

In Situ Nutrient Monitoring in the Murderkill Estuary


The Murderkill watershed is located in southern Kent County, Delaware and has a drainage area of approximately 270 km2. Based on a 2002 assessment, the land use in the watershed is predominantly agricultural (55%)  but like many coastal watersheds the amount of urban and residential development (14%) is increasing (Delaware  Department of Natural Resources and Environmental Control (DNREC 2005).

Tuesday, March 25, 2014
Product Manual

WQM Manual

Monday, December 23, 2013
SBC WQM Manual en.pdf
Scientific Poster

In Situ Estuarine Observatory to Evaluate Interannual Variability in Nutrient Dyamics

Wednesday, March 26, 2014
Koch and Barnard_Ocean Sciences 2014 posterv2.pdf
Technical Note

WQM X Dimensions

Thursday, October 31, 2013
WQM X Dimensions.pdf
Technical Note

WQM/ WQM X BLIS Technical Note

Thursday, October 2, 2014
Technical Note

Bulkhead Connector Care

Tuesday, February 10, 2015