How to Get Good Bacteria in New Fish Tank

It is essential to cycle a new aquarium before you introduce any animals. The purpose of cycling is to allow populations of nitrifying bacteria and other microorganisms to become established. Fish waste produces ammonia, which one group of bacteria process to nitrites. Ammonia and nitrites are highly toxic. A second group of bacteria convert the nitrites to the less-toxic nitrates, which plants and algae can absorb. Cycling happens naturally if you leave the tank long enough, but there are ways to speed up the process.

Things You'll Need

  • Aquatic plants
  • Water or used filter media from established tank
  • Bacteria culture
  • Fish food
  • Aquatic snails
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Instructions

    • 1

      Introduce aquatic plants to the tank to form the basis of a natural aquatic ecosystem. They also help process the fish waste later.

    • 2

      Add a pint of aquarium water from an established tank of the same type. For example, water from another cold freshwater tank or a tropical marine tank, depending on what type of aquarium you are setting up. A friend might have such a tank or you could ask in an aquarium supply store. Alternatively, ask for used filter media from an appropriate tank.

    • 3

      Add a culture of nitrifying bacteria if you couldn̵7;t find somebody with the right aquarium.

    • 4

      Add a couple of fish flakes to the water, to provide organic material for the bacteria to feed on before the introduction of animals.

    • 5

      Introduce a few aquatic snails after several days. The bacteria will process their waste and multiply.

    • 6

      Introduce fish two or three at a time after at least a week, allowing a gap of at least one week between each batch. The bacteria need to multiply sufficiently to process the waste of the fish you already have before you introduce new ones.