Alkalinity Problems in Aquariums

Alkalinity is the measurement of the amount of acid water can neutralize without changing its pH balance. Alkalinity exists in all types of water, from the ocean to a pool, drinking water or an aquarium. The majority of alkalinity in nature consists of carbonate alkalinity, from carbonate rocks or carbon dioxide on the surface of the water.

  1. Relating Alkalinity to Aquariums

    • A basic saltwater fish tank requires a pH level between 7.6 and 8.4, while a freshwater tank prefers a neutral level of 7.0. In particular, saltwater aquariums are extremely delicate systems that require an appropriate pH level.

      Acids may bring the pH balance lower than the appropriate range. The water in the tank contains chemicals that act as buffers to the acids, slowing the drop in pH. The number of buffers in the water determines the alkalinity. Optimal alkalinity will keep the pH level stable even with the steady addition of acids.

    Daily Management

    • Simple maintenance can keep the pH level of your aquarium stable and prevent alkalinity problems. Acids in the tank come primarily from excess carbon dioxide, nitrification and organic acids from metabolic waste. Keeping the tank free of fish waste and uneaten food can help minimize the amount of regularly occurring acids. In addition, doing a partial water change every other week will refresh the natural buffers in the water.

    Do-It-Yourself

    • Even with aquarium maintenance, alkalinity problems can still occur. To raise the alkalinity of the water, add 1 tsp. of baking soda for every 10 gallons of water. Keep in mind that changing the level slowly will be a less traumatic change for your fish. Checking the pH level and alkalinity level daily will help you keep control of your aquarium.

    Calcium Reactor

    • A calcium reactor can control radical pH and alkalinity problems --- the best way to maintain the health of the aquarium. However, they are more expensive and can cost anywhere from $20 to $390.

      Calcium reactors help maintain an appropriate level of calcium to alkalinity. They constantly monitor the alkalinity and pH level and immediately adjust accordingly.

      Calcium reactors require much less maintenance than checking the alkalinity and pH levels and adjusting with additives daily. They take the guesswork out of maintaining an aquarium.