How to Make Good Aquarium Bacteria

In its natural habitat, fish are unaffected by the build up of chemicals like ammonia or nitrite. Mother Nature takes care of it, keeping things on an even keel. However, take that same fish and put them in an aquarium and you have got another story all together. Mother Nature has been replaced by you, and if you don't watch things carefully the entire system will become toxic. There is more to keeping an aquarium than filling a tank full of water and dropping some fish in. You need to consider other factors, such as heating, lighting and filters. The main task of the filter is to remove rubbish from the water. But that not its only function. A filter also removes harmful chemicals from the aquarium environment. This secondary function is made possible by the growth of beneficial bacteria within the filter. The growth of these good bacteria is crucial to the health and well-being of your fish. The guidelines below can help you establish a population of good bacteria within your aquarium.

Things You'll Need

  • Commercial de-chlorination product
  • Water test kit
  • Starter fish
Show More

Instructions

    • 1

      Seed your aquarium with good bacteria. Use gravel or filter media from an established and healthy, tank. Make sure that the tank you are borrowing from has been up and running for at least two months. Squeeze the water from the filter sponges onto yours and scoop out some of the gravel and tank water. Keep the materials wet and transfer them to your system.

    • 2

      Fill the tank with water and remove the chlorine with a commercial de-chlorination product. Chlorine directly inhibits the growth of beneficial bacteria, disrupting the nitrogen cycle and creating an unhealthy environment for your fish.

    • 3

      Test the water in the aquarium. Follow the instructions on your water testing kit to check for appropriate pH, the presence of chlorine and for the presence of nitrates. The majority of kits will have you place a few drops of a testing solution into a vial of water from your tank. If the test substance is present, the water should undergo a visible color change.

    • 4

      Wait 48 hours to allow the temperature to become constant and allow your tank to settle, giving the bacteria a chance to establish themselves.

    • 5

      Add live plants as they will aid in the balance of the overall system.

    • 6

      Add starter fish. Choose economical varieties, such as guppies and mollies, or those known for their hardiness or ability to adapt to less than ideal conditions, such as tetras and tiger barbs. Add two fish, approximately 1 inch in length, for every 10 gallons of water in your tank. Be aware that you are placing them into unfavorable conditions and there is a high likelihood of them dying.

    • 7

      Wait 24 hours and test the water again. As the fish defecate, the amount of ammonia in the water will rise. As the good bacteria, Nitrospira, take root, they will feed on this ammonia. When the Nitrospira begin to grow, you will start to see a positive result when you test the water for nitrate.

    • 8

      Change part of the aquarium water out every other day. Remove approximately 25 percent of the water and replace it with new for six weeks to keep the level of ammonia from becoming toxic. Remember to remove the chlorine from the water before adding it to the aquarium.

    • 9

      Check the water every day. When you no longer get a positive result for ammonia and nitrite, you will have established a balanced ecosystem with an appropriate level of good bacteria working in your filter.