H2Ocean True Seawater Refractometer is a high-precision optical refractometer designed specifically for the ionic composition of natural seawater. Unlike standard “brine” refractometers, which are calibrated for sodium chloride solutions, this model provides true seawater-corrected readings, ensuring consistent and reliable results for reef aquariums where salinity stability is critical.

The refractometer features a clear, easy-to-read scale and high-contrast display, allowing quick measurement even under low-light sump conditions. A durable metal body, smooth focusing ring, and automatic temperature compensation (ATC) make this instrument robust, accurate, and user-friendly for daily or weekly water testing.

When preparing or adjusting saltwater using premium reef salts such as H2Ocean Classic Formula Salt , this refractometer allows you to accurately measure salinity and fine-tune salt levels to achieve consistent, repeatable results during water changes and top-ups.

This refractometer is calibrated for use at 20 °C (standard room temperature), ensuring stable, consistent, and accurate seawater readings under normal aquarium testing conditions.

Clear and Easy-to-Read Scale The high-contrast measurement window provides excellent readability, and the scale is deliberately concentrated over the small salinity range used in reef aquariums. This tighter span makes it much easier to pinpoint the correct value quickly and accurately.

Key Features

• True seawater calibration — accurate for marine ionic composition
• Automatic Temperature Compensation (ATC) for reliable readings
• High-contrast, easy-to-read measurement scale
• Durable, precision-built metal body
• Smooth focusing and comfortable eyepiece
• Ideal for reef tanks, fish-only systems, and seawater preparation
• Includes protective case, dropper, and calibration screwdriver

For more information about this product, please visit the official D-D product page:
https://www.theaquariumsolution.com/product/3034/123