Things You'll Need
- Aquarium
- Water hardness test kit
- Water hardness products
Instructions
Determine what hardness level the cichlids you plan to purchase do best in. This information can be found in a variety of places, including fish keeping books and guides. You can also ask the staff at your local aquarium center about recommended hardness levels.
Fill your aquarium and allow it to sit for a few days. Use a commercial water hardness test kit to determine the natural hardness level of your aquarium. It is best to take a reading each day over a three- or four-day period, then average those values together, since pH can fluctuate a bit.
Purchase materials designed to make the water harder. These water-hardening materials include calcium carbonate, calcium sulfate and magnesium sulfate. These materials are available at many pet stores and aquarium centers, and they are generally sold as powders that are dissolved into the water.
Add a small amount of the hardening materials into the water, then measure the hardness until it is at the optimal level. You will need to add more material each time you perform a water change to keep the water at the desired hardness level.