How to Mix Brackish Water

There are many fish that do best in brackish water conditions. Brackish water is a mixture of sea water and fresh water, common where two bodies of water with the opposite composition meet. There are fish that can survive in fresh and brackish water, although they must be gradually acclimated.

Things You'll Need

  • Sea salt
  • Tap water
  • Hydrometer
  • Large bucket
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Instructions

    • 1

      Remove fish from the tank if you are mixing new water during an aquarium water change.

    • 2

      Research what percentage of salinity of brackish water is appropriate for your fish. If you have fish that requires one-tenth saltwater, then fill your aquarium up 90 percent. You can calculate how much to fill your aquarium by using gallons divided by the percentage of salt water needed by the fish.

    • 3

      Mix the sea salt with the water you will be adding to fill the rest of the tank once you have partially filled the tank. For example, you would mix 10 gallons of saltwater for a 100 gallon tank if you need 10 percent saltwater. Follow the directions on the sea salt container measuring the correct amount of salt per gallons of water.

    • 4

      Add the mixed saltwater to the aquarium. Put a hydrometer, in the tank letting it settle so it can read correctly. Add water or remove water to adjust the salt level until you reach the desired measurement.