How to Get Good Bacteria in Freshwater Tanks

The water in a fresh water fish tank is not chlorinated and relies on bacteria to dispose of the fish waste. If you want to start a new aquarium, you will need to develop the good bacteria before putting fish in the tank to avoid fish death because of the undisposed waste. The first thing you will have to do is cycle the water to evacuate all the chlorine, then add good bacteria and finally test the water to determine when you can add the fish.

Things You'll Need

  • Nitrate
  • Nitrite and ammonia testing kit
  • Pure ammonia
  • Drop bottle
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Instructions

    • 1

      Install your aquarium equipment such as a pump, light, filter and air-pump and heater. Fill the tank with water and leave the filter, light and air-pump on 24 hours a day. Set the heater to 85 degrees Fahrenheit.

    • 2

      Let the equipment run for three or four days.

    • 3

      Add good bacterias to your tank. You can purchase bacteria from a fish store or take some water from a running, older fresh water aquarium.

    • 4

      Add ammonia one drop at a time. Each time you add a drop, mix the water and do a reading with your ammonia kit. Add drops until the concentration reads 5 ppm (parts per million). Write down the number of drops it took you to reach 5 ppm.

    • 5

      Measure the nitrite in the tank each day. Each day add the same number of ammonia drops you put in the first day. Do this until your nitrite reading is above zero.

    • 6

      Add half of the drops of ammonia to your tank each day after measuring the nitrite. Repeat until both ammonia and nitrite are zero.

    • 7

      Empty the aquarium, leaving just enough water to cover the gravel. Replace with clear water and let the filter run for an hour. Measure the nitrite level. If the levels are above 10, change half the water. If the levels are above 35, change all the water. Your cycling is finished when the nitrite levels are 10 or below.