Collection: Hydrometers & Refractometers

Test Salinity With Something You Trust

Salinity shifts daily as water evaporates, which makes it the parameter most worth measuring accurately — and the one where tool technique matters as much as tool choice.

Three Ways to Measure

• Swing-arm hydrometers — cheap and fast, and fine when kept clean. Rinse and dry after each use; bubbles and salt buildup are what throws them off.
• Glass floating hydrometers — a lab-style float that gives repeatable results when the sample sits at its stated reference temperature.
• Optical refractometers — a couple of drops on the prism reads directly, and the unit can be recalibrated over time.
• Calibration solution — a known seawater reference for checking a refractometer instead of assuming it's right.

Read at a consistent temperature and verify against a standard periodically. Questions? Email info@jlaquatics.com.