Great Aquariums Start Here
1-800-566-3474
Live Chat Support
    Free Shipping On $175+
  • FREE Shipping On $175+
  • 14-Day Low Price Guarantee
  • 14-Day Low Price Guarantee
  • Same Day Shipping
  • Same Day Shipping
FREE Shipping on Orders Over $175
FREE Shipping on
Orders Over $175
Standard ground shipping (1-7 business days) starts at a low $5.99 and most orders over $175 ship FREE. Learn More
14-Day Low Price Guarantee
If you find a product we sell for a lower price at another online store, we will match their price—today and up to 14 days after you've purchased the item! Learn More
Same Day Shipping
Same Day Shipping
We promise to ship your order as fast as humanly possible. In fact, 99% of orders placed before 6 pm EST ship the same day! Learn More
Show: per page
Grid View Grid List View List
Sort by:
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
American Marine Pinpoint pH Probe

American Marine Pinpoint pH Probe

PINPOINT ™ pH Replacement Probe is designed especially with your purpose in mind. It features long, continuous duty expectancy, fast response and, most importantly, is non-toxic to your system. Each probe features a 10 foot ca...

$39.99
Hanna Instruments Checker pH Pen

Hanna Instruments Checker pH Pen

High accuracy with 0.01 pH resolution Two point fast and accurate calibration Usable with virtually any electrode that shares the same connector 3000 hours of battery life HI 1270 small diameter probe fitseasily into a ...

$39.99
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 I/O Break Out Box for Apex, Apex Lite, AquaController 3, or AquaController 3 Pro

Neptune Systems I/O Break Out Box for Apex, Apex Lite, AquaController 3, or AquaController 3 Pro

Easily add float switches, water on the floor sensors, etc. to the Apex, Apex Lite, AquaController 3, or AquaController 3 Pro. Simply plug the Breakout box`s minidin 8 cable into the AquaController I/O port, and then attach the fl...

$39.95
Digital Aquatics pH Probe w/ Calibration Packets

Digital Aquatics pH Probe w/ Calibration Packets

Digital Aquatics pH Probe w/Calibration Packets Resolution 0.01 pH Cable Length 4 feet Connection Type Male BNC Included Calibration Packets 1 x 7pH calibration packet 1 x 10pH calibration packet Manufacture...

$39.99
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 Magnetic Probe Rack (MPR)

Neptune Systems Magnetic Probe Rack (MPR)

The newly announced MPR - Magnetic Probe Rack is the perfect product for anyone with an existing Apex or those just now picking one up. The MPR has four locations for probes so customers can rig up their pH, ORP, salinity, and tem...

$39.95
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
American Marine Pinpoint Wireless Thermometer (includes one sensor)

American Marine Pinpoint Wireless Thermometer (includes one sensor)

American Marines Wireless Thermometer Utilizing a radio wave signal, the remote sensor(s) will measure the temperature at the waterproof probe tip and send the information to the PINPOINT Temperature Display Monitor, which will d...

$34.49
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
Digital Aquatics RKM-HUB Bus System

Digital Aquatics RKM-HUB Bus System

5 x Bus Ports The HUB has 5 bus ports for easy expansion when the traditional daisy chain is not an option. 1 x Power Port 9VDC input voltage for providing additional power to your system. Tech Specs LED Status Indic...

$39.99
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
American Marine pH/ORP Extension Cable

American Marine pH/ORP Extension Cable

American Marine pH/ORP Extension Cable PINPOINT 15 foot extension cable for the pH or the ORP/REDOX probe. This will add an additional 15 feet onto the 10 feet of the probe cable for a total of 25 feet. This extension cable wil...

$34.99
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
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
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
Hanna Instruments Replacement Electrode for DiST 5 Waterproof Low Range EC/TDS/Temperature Tester

Hanna Instruments Replacement Electrode for DiST 5 Waterproof Low Range EC/TDS/Temperature Tester

Hanna Instruments Replacement Electrode for DiST 5 Waterproof Low Range EC/TDS/Temperature Tester

$55.49
This item is temporarily unavailable but will be back in stock soon.

Item #
Price:
Click the Add To Cart button below if you'd like to reserve this item today. Any other items included in your order will be immediately processed and shipped. We will ship this item separately as soon as it arrives. We will not charge you for this item until it ships and you will incur no additional shipping charges.

Enter your email address in the field below and click the Notify Me button if you'd like us to send you an email when this item becomes available. Although you will be immediately notified when we have stock on hand, we will not reserve any units for you; you must return to our website and place an order.

Your Email:
Just enter your email address below and we'll let you
know when the product you are looking for becomes available!

Item Code:
Price:
Your Email:
Marine Depot Newsletter Signup
Aquariums, News & Culture
Join 100,000+ readers who receive weekly tips, videos, deals and giveaways.