How to Adjust a Calcium Reactor

The coral reef aquarium is one of the most complex aquatic systems to balance in a home aquarium. Your calcium reactor can save you money over adding liquid or solid supplements to balance the calcium, magnesium, alkalinity and pH of the artificial seawater. But to get the most from your investment, you'll need to adjust the flow of effluent---the material returning to the tank from the calcium reactor---and/or the flow of carbon dioxide (CO2) into the calcium reactor until it replaces the minerals used by your reef at the same rate they are metabolized by your corals. Alkalinity is affected by the ions returning to the tank water from the calcium reactor effluent along with the dissolved calcium. Measuring alkalinity and pH will give you a more accurate measure of whether enough calcium is entering the tank or not than simply testing for calcium levels.

Things You'll Need

  • Aquarium pH test kit Alkalinity test kit
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Instructions

  1. Alkalinity Tests Low

    • 1

      Test the aquarium water for pH and alkalinity levels after allowing the calcium reactor to run for at least 24 hours.

    • 2

      Lower the pH of the effluent by increasing the rate of CO2 into the calcium reactor. This increase in acidity increases the dissolution of calcium inside the reactor and will increase alkalinity in the aquarium water.

    • 3

      Increase the effluent flow from the calcium reactor if the pH inside the reactor is 6.5---you don't want it much lower than that, depending on the media used inside the reactor.

    Alkalinity Tests High

    • 4

      Test the water for pH and alkalinity levels, after allowing the calcium reactor to run for at least 24 hours.

    • 5

      Disconnect the calcium reactor to allow high alkalinity levels to return to your target levels before adjusting the effluent or CO2. Wait a few hours.

    • 6

      Decrease the rate of CO2 into the reactor.

    • 7

      Decrease the effluent flow into the tank from the calcium reactor.