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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
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
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
Digital Aquatics RKM-PC4

Digital Aquatics RKM-PC4

IntellaStrip Technology Our new PC4 is the most advanced power distribution unit in the industry with the ability to keep your system up and running even if you have a device failure. Manual Override Mode Gives you ...

$89.99
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
Neptune Systems ORP Probe

Neptune Systems ORP Probe

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

From $69.95
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 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 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
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
Hanna Instruments Waterproof pH Tester with Replaceable Electrode

Hanna Instruments Waterproof pH Tester with Replaceable Electrode

When HANNA instruments introduced its first version of the pHep (pH electronic paper) in 1986, it immediately revolutionized the standard in pH measurement. pHep`s ease-of-use in combination with its affordability made it possible...

From $88.99
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
Won Brothers PH D-1500 Temperature Controller

Won Brothers PH D-1500 Temperature Controller

The Won Brother PH D-1500 temperature controller can be used with heaters, heating elements or chillers. This single-stage temperature controller can be used with heaters up to 1500W or chillers up to 3/4HP. The controller include...

$89.99
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
HM Digital COM-80 HydroTester EC/TDS Meter

HM Digital COM-80 HydroTester EC/TDS Meter

EC/TDS/Temp Water Resistant Hydrotester The COM-80 is an economically priced, reliable EC/TDS meter that is ideal for testing applications such as hydroponics & gardening, pools & spas, aquariums & reef tanks, water ionizers, d...

$40.99
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
Hanna Instruments Primo TDS Tester

Hanna Instruments Primo TDS Tester

Direct probe connection Automatic calibration Automatic Temperature Compensation The Primo series of testers provide a fast and dependable way to measure the total dissolved solids or conductivity in your water samples. It...

$40.99
1 - 25 of 30
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