How to Change Fish Tanks

It happens to every fish hobbyist at some point. Your aquarium is too small or is the wrong kind for the fish you want to keep, and you need to change it for a new one. The prospect of changing fish tanks can be daunting at first, but with the right tools and preparation, the task can be managed with little mess or inconvenience.

Things You'll Need

  • Large buckets or bottles (enough to hold the water in your tank)
  • Siphon
  • Net or cup
  • Dinner plate
  • PH drops or mix
  • Aquarium thermometer
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Instructions

    • 1

      Begin to siphon water from the tank into the buckets or bottles. Siphon off as much as possible-until there are only a few inches left at the bottom. Retain the water to use in the new fish tank.

    • 2

      Catch all of the fish with a net or cup and put them in one of the containers of tank water. Keep this container away from any pets or small children to reduce the stress on the fish during the tank change.

    • 3

      Remove all decorations, filters, thermometers and any other items in the tank. Then remove any rocks as well as the gravel or sand (called substrate) covering the bottom of your tank.

    • 4

      Remove the old tank and set up the new one. If you plan to keep the old tank, you'll need to rinse and dry it before you store it.

    • 5

      Set up the new tank and begin putting all of your items into it. Start with the substrate, then position the rocks and decorations.

    • 6

      Place the dinner plate in the bottom of the tank and the pour the water onto the plate to put it back into the tank. The plate keeps the water from stirring up the substrate. Pour in all of the water, except for the water in the container holding your fish.

    • 7

      Scoop the fish out of their container and release them into the tank. Pour out the water they were in and replace the water with new, treated water. Be sure the water you replace is at the same pH level and temperature as the rest of your tank.