How to Use Crushed Seashells to Raise the pH of a Freshwater Aquarium

The ecosystem of an aquarium must be carefully maintained to provide the best living environment for fish. The needs of your fish must be considered and every effort must be made to accommodate them. One very important environmental factor is the hardness of the water. Hard water has high levels of calcium and a high pH, and is suitable for cichlids, freshwater soles, halfbeaks, glassfish, puffers, and more. If you want to raise these fish, you need to ensure that your water is hard enough. You can adjust the pH of tap water by adding crushed seashells, a natural source of calcium.

Things You'll Need

  • pH Meter
  • Aquarium
  • Crushed Seashells
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Instructions

    • 1

      Dip the probe end of the pH meter into the aquarium water. The meter will begin collecting data, which takes a moment. The meter will display a reading on the LCD display once it has collected enough data. If this reading is below pH 7.4, you need to raise the pH by adding crushed seashells.

    • 2

      Pour a small amount of crushed seashells into the water. If the pH is below 7.4, the seashells will dissolve. Pour more seashells in until they stop dissolving. At this point, the seashells have raised the pH to 7.4 and will act as a buffering agent. This will keep the pH level stable over time.

    • 3

      Take another pH reading using the pH meter. Verify that the pH is 7.4. If it isn't, try adding some more crushed seashells but this time give them more time to dissolve.