How to Convert a Salt Fish Tank to a Freshwater

Saltwater aquariums are beautiful, but they're often more difficult to maintain than freshwater aquariums, not to mention that the animals are a tad pricier. If you'd like to convert your saltwater aquarium to a freshwater aquarium, you have to completely strip the aquarium down. You'll have to clean it from top to bottom, and the components and decor from the inside out, to get rid of all evidence of saltwater animals, because their leftovers may kill the freshwater animals. Once you've cleaned it, then the aquarium will be ready for the freshwater conversion.

Things You'll Need

  • Vinegar
  • Bleach
  • Scrubbing pads
  • Pipe cleaners
  • New aquarium decor
  • New filtration system (optional)
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Instructions

    • 1

      Remove all the animals, if there are any. If the animals are healthy, make gifts of them to somebody with a saltwater aquarium or give them to a local pet store that is willing to take them.

    • 2

      Fill a large bucket with water and bleach. The more bleach, the better.

    • 3

      Disconnect the electrical components of the filtration system from their power sources and remove the filtration system from the aquarium.

    • 4

      Discard all the filter pads.

    • 5

      Remove all the aquarium decor. You should keep only items that you can thoroughly clean. Throw away any plants in the aquarium and the aquarium floor (rocks, gravel, or any other type of substrate).

    • 6

      Remove the plastic underlayment (the part of the filtration system that is underneath the aquarium floor).

    • 7

      Soak the filtration system and all the other salvageable things -- pieces of decor and the plastic underlayment -- in the bleach water.

    • 8

      Dump out the water in the aquarium. For large aquariums, you may need some extra muscle (assistants) to help with lifting or you can use a high-powered water vaccuum to suck out the water.

    • 9

      Scrub the inside of the aquarium with vinegar and scrubbing pads. Bacteria and other organic material will remain inside the aquarium from the saltwater animals. Their organic material will kill freshwater animals, so you have to scrub the aquarium very thoroughly.

    • 10

      Rinse the aquarium very thoroughly. You want any organic material and the vinegar out.

    • 11

      Clean the items you placed in the bleach water. Scrub them all over. When cleaning the filtration system components, use pipe cleaners to get the grime out of hard-to-reach places.

    • 12

      Rinse the bleach off the filtration system and decor. When the bleach smell is gone, the items are ready for use.

    • 13

      Replace the plastic underlayment and the filtration system. If the saltwater filtration system isn't compatible with a freshwater environment, you'll have to purchase a new filtration system.

    • 14

      Decorate the aquarium with a new floor and the decorative items you cleaned in the bleach water.

    • 15

      Fill the aquarium with water.

    • 16

      Connect the filtration system components to power sources and let it clean the water.

    • 17

      Drop the freshwater animals in the water while they're still in their plastic bags when the water reaches a temperature of about 70 degress Fahrenheit. This allows them to get used to the temperature before they're actually inside the water.

    • 18

      Release the animals from their bags and enjoy your freshwater aquarium.