DIY Aquarium Chillers Using a Refrigerator

Aquarium chillers can cost several hundred dollars, and sometimes even thousands. If you have a spare refrigerator around, you may have considered converting it to work as a chiller when the temperature in your aquarium rises. This can be done, but it is a challenging project. Keep in mind that the electrical load from your refrigerator will be substantial, so you should make arrangements to ensure that you do not blow a fuse.

Things You'll Need

  • Cold refrigerator
  • Underwater circulating (pond) pump
  • Plastic tubing that fits the pump
  • Drill
  • Drill bit that fits the tubing
  • Drill bit wider than the pump plug
  • Round file
  • Spray foam insulation
  • Non-toxic cleaner
  • Water
  • Salt
  • Bucket
Show More

Instructions

    • 1

      Drill two holes through the refrigerator door for the tubing. File the sides of these holes to remove sharp edges that may puncture the tubing. Drill a third hole for the pump's power plug to come out of the refrigerator and reach a power outlet.

    • 2

      Feed the tubing through the holes to create a loop outside the refrigerator. This loop should be long enough to reach and be submerged in the fish tank. There should be approximately three feet of coiled extra tubing on each end inside of the refrigerator. Cut off the rest of the tubing.

    • 3

      Clean the section of tubing that will be submerged in the fish tank. Place it in the tank.

    • 4

      Put a bucket filled with salt, water and ice in the refrigerator.

    • 5

      Attach one end of tubing to the pond pump and place the pump in the bucket. Put the other end of tubing in the bucket. Feed the pump's power cord through the hole in the refrigerator door.

    • 6

      Use spray foam insulation to seal the hole in the refrigerator door around the power cord. Close the door.

    • 7

      Plug in the pump's power cord. This will circulate cold water through the tubing that is submerged in the fish tank. You do not need to replenish the ice in the bucket.