How to Convert a Salt Water Tank to Fresh Water

Many aquarium enthusiasts will one day make the decision to convert their aquarium from saltwater to freshwater. Whether it is because the saltwater hobby is too labor-intensive and expensive, or merely because the fish keeper wants to delve into something new, knowing how to clean and prepare the tank and supplies is critical to the health of your freshwater fish. With a little elbow grease, you can convert a saltwater fish tank can be quickly and cheaply converted to freshwater.

Things You'll Need

  • Garden hose
  • White vinegar
  • Sponge
  • Bucket
  • Filter pad
  • Aquarium gravel
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Instructions

    • 1

      Drain the saltwater tank and empty it of all of its equipment, decorations and substrate. Discard the filter pads and substrate, as well as any decorations made from coral skeletons, which will harm the pH in the freshwater tank. You can also put aside equipment such as protein skimmers and powerheads, which are not needed for a freshwater aquarium.

    • 2

      Rinse the tank and all of the equipment off with a garden hose to remove the majority of the saltwater and some of the surface residue and algae.

    • 3

      Mix 1 cup of household white vinegar in a bucket of warm water and wipe down the inside and outside of the tank and equipment to remove lingering salt particles. Scrub off algae with a sponge, algae scraper or old toothbrush dipped in the vinegar solution. Rinse everything with the hose again after scrubbing with vinegar.

    • 4

      Set up the tank and equipment inside, and fill the tank with dechlorinated tap water. Place a bag of activated charcoal in the filter, and run the entire setup overnight.

    • 5

      Drain the tank again.

    • 6

      Rinse the aquarium gravel (you will need roughly 1 lb of gravel for each gallon of tank) in a bucket until the water runs clean and add it to the bottom of the tank.

    • 7

      Add tank decorations and place new filter pads into the filter.

    • 8

      Fill the tank with dechlorinated tap water, and turn all of the equipment on.

    • 9

      Stock the newly converted freshwater tank slowly over the next few weeks, monitoring the pH, ammonia and nitrite levels carefully as the tank progresses through the nitrogen cycle. After the tank has been established for at least a month or two, you have little to worry about besides enjoying your freshwater aquarium.