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Duo-ORpH Aquarium Controller for pH and mV (ORP)

Reef Aquarium
Duo-ORpH ControllerDual monitoring of pH and ORP in large LED display and single control of either pH or ORP. Highly accurate.
  • Digital pH-ORP controller with large size LED display for easy reading.
  • High input impedance avoid measuring error.
  • Built in SLOPE and CAL. adjust knob, easy for single point or two points pH calibration.
  • "ON - OFF" control, the relay "ON" when measuring value is above the set point for pH.
  • And the relay "ON" when measuring value is below the set point for ORP.
  • Front LED lamp indicate when relay "ON".
The Duo-ORpH Controller is probably the least expensive dual controller on the market today. But don't be fooled by its price, it is extremely accurate. It does not have those bell & whistle features which you may not need. Nor do you have to read a novel-thick of instruction booklet to study the Solar & Lunar phases. Its control is very straightforward indeed. Buy either the pH or ORP probe (or both) for various applications. With the electrodes in place, it can monitor both the pH and ORP readings at all times while controlling either the pH- or ORP-related devices. If one needs only a pH controller, just buy the pH electrode with our controllers, and vice versa for the ORP application.
  • For Freshwater Aquarist - Get the Duo-ORpH Controller + Refillable Electrode to control CO2 system
  • For Marine Fish Aquarist - Get the Duo-ORpH Controller + Refillable pH & ORP Electrodes to control ozonizer and monitor tank pH
  • For Reef Aquarist - Get the Duo-ORpH Controller + Refillable pH & ORP Electrodes to control kalkreaktor and monitor ORP
Specifications:
  pH ORP
Measurement 0 to 14 pH -1999 to 1999 mV
Resolution 0.01 pH 1 mV
Accuracy at 25 C ± (0.01 pH + 1 digit) after calibration ± (1 mV + 1 digit)
Impedance 10E12 ohms 10E12 ohms
Control Range 3.5 to 10.5 pH 0 to 1000 mV
Calibration Knob External pH 4 (SLOPE) pH 7 (CAL.)  
Relay Contact 10A for 125V AC / 8A for 240V AC
Sampling Time 0.5 second
Display 0.5" LED, 3-1/2 digits
Operating Temperature 32 F to 122 F
Operating Humidity Max. 90% RH
Power Supply AC 110 V, ± 10%, 50/60 Hz
Power Consumption Approx. 2 watts
Dimension 5.9" x 3.4" x 1.6"
Weight 1.2 lb (incl. power cable)
pH Electrode BNC Connector
ORP Electrode BNC Connector
Reef Aquarium
Item #DescriptionPrice 
AQ3333Aqua Medic ORP Electrode$107.99
CP2133pH 4.0 Buffer/Calibration Solution 500 ml$11.99
CP2135pH 7.0 Buffer/Calibration Solution 500 ml$12.49
CP2137pH 10.0 Buffer/Calibration Solution 500 ml$11.99
AL3111Aqua Logic 1/2 inch Diameter Sensor Probe Holder w/ Suction Cup (1 piece only)$3.00
Note: Duo-ORpH Controller does not come with pH and ORP electrodes/probes. Each sold separately.

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