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1 - 25 of 26
Hanna Instruments Checker Colorimeter

Hanna Instruments Checker Colorimeter

The HANNA HI 711 Checker HC bridges the gap between simple chemical test kits and professional instrumentation. Chemical test kits are not very accurate and only give 5 to 10 points resolution while professional instrumentation...

From $49.99
Marine Depot Aquarium Refractometer

Marine Depot Aquarium Refractometer

The Refractometer is a must have for all aquarium hobbyists. The proper salinity is crucial for the survival and health of your fish and corals . This high quality refractometer is extremely accurate and easy to use and calibr...

$49.99
Marine Depot Aquarium Pro Refractometer

Marine Depot Aquarium Pro Refractometer

Designed specifically for aquarium use to measure the salinity of natural sea water (NSW). Most handheld saltwater refractometers available in the hobby are designed and calibrated for testing brine solution, i.e. sodium chlorid...

$64.99
Neptune Systems pH Probe

Neptune Systems pH Probe

Feature(s): Precision of +/- .01 10` coax cable Sealed Ag/AgCI reference. Standard BNC connector

From $44.95
Captive Purity Refractometer

Captive Purity Refractometer

The Captive Purity Refractometer is an incredibly accurate and easy to use device that eliminates the confusion associated with inexpensive hydrometers. Just place a couple of drops of water on the prism and hold to the light. Rea...

From $59.99
Neptune Systems Apex AquaController PM2 Conductivity, Temperature, I/O Expansion Box

Neptune Systems Apex AquaController PM2 Conductivity, Temperature, I/O Expansion Box

The PM2 probe module, includes support for conductivity (salinity), temperature, and 6 digital inputs. The PM2 features are: Monitor/Control Conductivity and temperature. 6 digital inputs for float switches, water on floo...

$84.95
Neptune Systems Apex AquaController PM1 pH or ORP, Temperature, I/O Expansion Box

Neptune Systems Apex AquaController PM1 pH or ORP, Temperature, I/O Expansion Box

The first expansion module, the PM1, with a pH or ORP, temperature, and 6 digital inputs. 4 in 1 goodness with this module! The PM1 probe module is just what you need if you want to monitor pH or ORP in your tank. And, the...

$84.95
Neptune Systems Advanced Leak Detection Module (ALD)

Neptune Systems Advanced Leak Detection Module (ALD)

The Advanced Leak Detection module easily connects to any Neptune Apex System (Apex, Lite, or Jr.) and gives you up to four locations of leak detection. Two different types of leak detection probes are available (sold separate...

$74.95
Digital Aquatics ReefKeeper Module RKM-SL2v2

Digital Aquatics ReefKeeper Module RKM-SL2v2

The RKM-SL2 is the newest System Lab module from Digital Aquatics. It's a big leap forward with fully (and individually,) isolated ph and salinity ports. On top of that, the Digital Aquatics salinity probe is equipped with full di...

$79.99
Neptune Systems ORP Probe

Neptune Systems ORP Probe

Feature(s): 10` coax cable Platinum band electrode. Standard BNC connector

From $69.95
Neptune Systems AquaBus Lunar Simulator Module (LSM)

Neptune Systems AquaBus Lunar Simulator Module (LSM)

The Lunar Simulator Module (LSM) allows the AquaController to control and vary the intensity to a 2 to 5 LSM Lunar LED String for a realistic moon cycle simulation. The moonrise and set times follow the true lunar cycle. LSM Lun...

$49.95
Neptune Systems Lunar Simulator LED String

Neptune Systems Lunar Simulator LED String

LSM Lunar LED String – 3 LEDs *Use this string of LED in combination with your Apex system and Lunar Simulation Module (LSM) When you purchase the Apex Controller and Lunar Simulation Module you need to outfit it with a ...

From $39.95
HM Digital PH-80 Handheld Digital pH Meter

HM Digital PH-80 Handheld Digital pH Meter

The PH-80 is an economically priced, reliable pH meter that is ideal for testing applications such as hydroponics & gardening, pools & spas, aquariums & reef tanks, water ionizers, drinking water and more. Featur...

$49.99
American Marine Pinpoint ORP Probe

American Marine Pinpoint ORP Probe

American Marine PINPOINT ORP Replacement Probe 10 foot cord Ag-Ag/Cl reference Platinum wire sensor Extended life High supression cable jacket

$74.99
Digital Aquatics RKM SL-1 Module

Digital Aquatics RKM SL-1 Module

Multiple Inputs The RKM-SL1s five input ports provide a broad range of monitoring options for all the most common probes. 1 x pH port: The pH port is a standard BNC connection. While any standard probe should work, we suggest u...

$69.99
Digital Aquatics ORP Probe w/ Calibration Packets

Digital Aquatics ORP Probe w/ Calibration Packets

Digital Aquatics ORP Probe Manufacturer: Digital Aquatics Resolution: 001mV One Male BNC Cable Length: 6 Feet (2 Meters) Probe Body: Dia 1/2" Probe Body: length 6.5" One Digital Aquatics ORP Probe One ...

$79.99
HM Digital Waterproof pH Meter

HM Digital Waterproof pH Meter

Professional Waterproof pH/Temp Meter Very reliable waterproof pH meter measures with an accuracy: of +/- 0.02 pH. Measures pH and Temperature Auto-ranging three point calibration with digital fine tuning Includes 4...

$79.99
HM Digital Waterproof EC / TDS / Temp Combo Meter

HM Digital Waterproof EC / TDS / Temp Combo Meter

COM-100: Waterproof EC / TDS / Temp Combo Meter Ideal for all water quality testing, water purification applications, wastewater regulation, aquaculture, hydroponics, colloidal silver, labs & scientific testing, pools &a...

$66.99
Hanna Instruments Replacement Electrode for HI98121, HI 98127, HI 98128, HI98129, HI98130

Hanna Instruments Replacement Electrode for HI98121, HI 98127, HI 98128, HI98129, HI98130

Spare electrode for HI 98121, HI 98127, HI 98128, HI 98129 and HI 98130

$55.49
Digital Aquatics Expansion Socket for ReefKeeper Controller

Digital Aquatics Expansion Socket for ReefKeeper Controller

Expansion Socket The Digital Aquatics Expansion Socket allows you to control high current devices without affecting your ReefKeeper power budget

$49.99
JBJ TrueTemp Digital Heater Controller

JBJ TrueTemp Digital Heater Controller

JBJ TrueTemp Digital Heater Controller JBJ`s TrueTemp digital heater controller is the most accurate & precise controller available. Plus/Minus 0.5F Accuracy 0-99.9F Temperature Range HIGH & LOW Temperature ...

$84.99
Hanna Instruments pH Electrode Ultem Body, Dbl Junction, Gel Filled, Teflon Junction, BNC, 1m Cable

Hanna Instruments pH Electrode Ultem Body, Dbl Junction, Gel Filled, Teflon Junction, BNC, 1m Cable

Spare pH electrode, with Teflon ® junction, 2 m (6.6') cable, for general purpose, water treatment and agriculture.

$51.49
Oxyguard Calibration Kit

Oxyguard Calibration Kit

Calibration kit for Neptune AquaController Dissolved Oxygen Probe.

$69.95
Neptune Systems Temperature Probe - used for AquaController Pro Only

Neptune Systems Temperature Probe - used for AquaController Pro Only

Feature(s): Precision of +/- 0.1F 6` cable. High quality probe w/ 6` cable Encapsulated thermistor 2.5mm Phono Jack Connector

$59.99
Digital Aquatics RKM-DCI DC Pump Interface

Digital Aquatics RKM-DCI DC Pump Interface

DC Pump Control... now available with all ReefKeeper systems! The new DCI module allows you to expand your existing ReefKeeper system even further - offering full control over 24V direct current (DC) pumps that use round 3-pi...

$59.99
1 - 25 of 26
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