YSI 900 Chlorine Colorimeter


YSI 900 Chlorine 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.

The 900 colorimeter is a rugged, waterproof, single parameter instrument for the measurement of Total chlorine or Free chlorine. Whether you need to measure chlorine in wastewater, chlorine in groundwater, or in pools, this chlorine tester is waterproof with an easy to read display and will provide readings in minutes.

Already measuring chlorine? Receive 20 free packets of DPD Free Chlorine or DPD Total Chlorine! Get your free samples. You might also be interested in learning more about our trade in program currently going on (U.S. only). Or, if you prefer to buy from one of our dealers, take advantage of our rebate program!

The instrument features a real time clock, automatic data logging as well as the ability to export data to a PC or printer using the 900 Series Data Hub for infrared data transfer.

Features for the 900 to quickly and accurately measure Free or Total Chlorine include:

  • Automatic data storage; 16 data-sets with date and time stamp
  • Large, backlit LCD display
  • IP68 waterproof case; easy to hold or set on benchtop; floats
  • Innovative light shield avoids moving parts or separate pieces that can easily be broken or lost
  • User-calibration to any government or organizational standard (for example N.I.S.T. or ISO)
  • Resolution can be improved for specific range requirements
  • Known interferences can be adjusted for the sample
  • Auto shutoff extends battery life
  • 2-year warranty

You can rely on the accuracy and reliability of YSI 900. Includes 100 powder packs of each (Free and Total chlorine). Start getting chlorine results today.

The 900 includes hard-sided carrying case with compartments for the instrument, accessories, reagents, and more.

If you are interested in measuring multiple parameters or COD only, then you may be interested in the YSI pHotoFlex colorimeters or the YSI 910 COD.


Benchtop Yes
Certifications IP68 (1 hour at 0.1 meter), floats, CE
GLP Compliance Yes
Measurement Range Chlorine Free: 0.02 to 2.0 mg/L, Chlorine Total: 0.1 to 8.0 mg/L
Memory 16 data sets with date and time stamp, automatic
Parameters Measured DPD Free Chlorine, DPD Total Chlorine
Power approximately 17 continuous hours or 5,000 tests, 4 alkaline AAA batteries
Sampling Yes
Unit of Measure mg/L
Warranty 2-year instrument


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