Brightwell Aquatics Refractometer & Hydrometer Calibration Standard 250ml (RES250)

Product details

Brightwell Aquatics Refractometer & Hydrometer Calibration Standard 250ml (RES250) is a precision reference solution used to calibrate seawater refractometers, hydrometers, and other density measuring equipment for marine aquariums. It provides a consistent standard so your salinity/specific gravity readings are aligned with the intended target value, helping you fine-tune reef and saltwater systems more confidently.

Features:

• Calibrates refractometers and swing-arm hydrometers for saltwater salinity testing.
• Target reference values are stated for marine use: 35 ppt salinity and 1.026 specific gravity (at 25°C).
• Formulated as a laboratory-quality standard fluid to support consistent, repeatable calibration.
• Includes value guidance for both equipment types, supporting accurate tool verification during normal maintenance.
• Made for aquarium hobbyists who rely on density measurements to manage saltwater aquarium conditions.
• 250 ml size for ongoing calibration needs.
• Simple use: shake the product well before using and allow appropriate wait time for refractometer readings.

Specifications:

• Product name (shop listing): Brightwell Aquatics Refractometer & Hydrometer Calibration Standard 250ml (RES250)
• Intended use: Calibration standard for seawater refractometers, hydrometers, and other density measuring equipment
• Volume: 250 ml
• Salinity standard: 35 ppt (at 25°C)
• Specific gravity standard: 1.0264 (at 25°C)
• Refractive index: 1.3394
• Conductivity: 53 µS/cm (at 25°C)
• Ingredients (as listed): High purity salts
• Refractometer calibration reference: Wait 45 seconds and calibrate to 35 ppt salinity