Aquarium Hydrometer


We tested every single hydrometer on the market and this one is by far the most accurate and easy to use. We still prefer a refractometer but more a cost effective option that we stand behind, go with this aquarium salinity hydrometer.

Key Features

  • Easy to use
  • Large easy to read scale
  • Precise within +/- 1.0 SG
  • Durable clear acrylic for years of use

Before using this salinity aquarium hydrometer being by soaking it in saltwater for 24 hours.

Step 1 – Slowly fill the  Hydrometer by dipping bottom corner fill port below water surface until water flows up and over inner weir.

Step 2 – Dislodge air bubbles by gently tapping hydrometer or pointer. Air bubbles on the pointer may result in inaccurate results.

Step 3 – Place the hydrometer on a level surface and read specific gravity (inside scale) and salinity (outside scale).

Rinse thoroughly in freshwater after each use to prevent mineral/salt buildup which can affect accuracy.

Reef casa recommends keeping your salinity range from 1.024-1.026 ppt