
Refractometer
400115
The Waterbox Refractometer is designed for testing the concentration of saltwater. Its triple scale provides a direct reading of the specific gravity and concentration (Parts per Thousand) of salt in...
Or build it into a bundle — save up to 6% ↓What it is, and who it is for.

The Waterbox Refractometer is designed for testing the concentration of saltwater. Its triple scale provides a direct reading of the specific gravity and concentration (Parts per Thousand) of salt in water. It provides reliable refractive index and salinity readings of total dissolved solids of aqueous solutions.
The Waterbox Aquariums® Refractometer is ideal for measuring salinity in saltwater aquariums. Whether monitoring your aquarium's salinity or mixing a new batch of saltwater, a refractometer is a must-have for every saltwater aquarium owner.
Designed for Saltwater Aquariums
A common mistake hobbyists make is purchasing a refractometer designed to measure salinity in brine. Using the incorrect Refractometer will give you incorrect readings. Our Refractometer is designed to measure seawater and will provide accurate readings whether you are testing your aquarium or a new batch of saltwater
Features
- Designed specifically for measuring seawater
- Dual measurements in SG or PPT
- Integrated Automatic Temperature Compensation
- Includes case, dropper, screwdriver, user manual and cleaning cloth
- 2 Year Standard Warranty
Build around the Refractometer.
It's already in your system below. Add the flow, filtration and dosing around it and the discount starts working — tiers climb as the build grows, and the reef meter fills with it.
Pick the right one, not the biggest one
The honest line-up from test kits. Most buyers reading this page should buy the middle column.
Asked before checkout
The questions our support inbox actually gets.
Does it ship quickly?+
Orders placed before 2 PM ET on a business day leave the same day. Tracking is emailed the moment the label prints.
What if it's the wrong fit for my tank?+
Return it. 30 days, no restocking fee, refund to the original payment method. Better: tell us your tank first and we'll spec the system for free — half of all returns are sizing problems.
Who handles the warranty?+
We do. Everything carries the manufacturer's warranty and we run the claim for you — one email to us instead of a ticket queue.
How does the bundle discount work?+
Add items in the bundle builder: 2+ items saves 5%, 3+ saves 8%, 4+ saves 12%, and 5+ saves 15% off the whole system, applied at checkout.

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