Salinity is the level of salt within your aquarium.
*PPT = Parts Per Thousandth*
  • Freshwater is measured as between 0 and 0.850ppt
  • Brackish water is measured as between 1.000 and 1.010ppt
  • Salt water is measured as between – 1.020 – 1.030+
The average marine aquarium will require a consistent salt level of between 1.024 and 1.026ppt.
This can be measured through the use of a refractometer. The first and most important step would be to calibrate your refractometer at 0 by using RO.DI (Reverse Osmosis De-Ionised) water. This will calibrate the level at 0. This will ascertain an accurate reading.
You would then, using a pipette, sprinkle (or lightly dip) saltwater to cover the lens of the refractometer, closing the cover and pointing the refractometer onto a white source of light.
Looking through the eye-piece, you would peer into the refractometer, where you would see the contrast line (blue vs white). This would tell you what salt level of your aquarium is.

We stock Marine, Tropical and Pond Salts. We also stock Salinity refractometers to help you create your ideal set up. Click here to see the range.