How to Make Artificial Seawater

Start your aquarium out healthy by making artificial seawater.

Artificial seawater is composed of more than just sodium chloride, also including additional minerals found in natural seawater. It is important to obtain a balance of these minerals in your tank. Before beginning the process of making artificial seawater, it is important to decide exactly how you want to execute your aquarium. Planning your aquarium's filtration system, type of substrate, lighting system and heating system as well as testing them before you begin to mix your artificial seawater saves you both time and money.

Things You'll Need

• Salt water mix
• pH meter

Instructions

1. Do a test run of your aquarium using freshwater. Fill the tank, and allow the water to cycle through the filtration system to guarantee the equipment is in working order.

2. Determine which commercially available salt water mix is best for your aquarium. Compare the amounts of minerals and salts in different products to the amounts found in natural seawater. If you are making a reef-only tank, there are also artificial mixes suited to that as well.

3. Purchase the artificial seawater mix of your choice. Most products are available at pet and aquarium stores or can also be ordered online.

4. Add the salt water mix to your tank using the amount indicated on the package for the size of your tank. It is important to do this before adding the freshwater because adding the water first can cause a high concentration of minerals.

5. Add the freshwater to your tank, following the manufacturer's directions.

6. Allow the water to cycle through the tank for at least 24 hours.

7. Test the pH and salinity of the tank, using pH test strips. Compare the mineral levels to those found in natural seawater.

8. Adjust for high or low concentration of minerals. Generally, pH and salinity levels should be relatively close to natural seawater as long as the proper amount of mix is used. However, for a high concentration of minerals, add more freshwater to the tank. For a low concentration of minerals, add more mix.

9. Allow the water to cycle for 24 hours after adjustment before retesting.

10. Install your reef and fish after the proper balance has been established.

Tips & Warnings

• Continue to check the pH and salinity of your tank every week after setup to maintain a healthy tank.

References

• Debbie and Stan Hauter: Major and Minor Elements in Natural Sea Water
• JSTOR: Limnology and Oceanography--Preparation of Seawater