How to Repair an Aquarium Fish Tank

Damage to aquariums can occur through routine maintenance. Some damage, such as cracks in the glass walls, can make a mess in your house and threaten the lives of your fish. Fortunately, repairing a cracked aquarium is a simple process with the right equipment, and it is a much cheaper alternative to purchasing a new aquarium.

Things You'll Need

  • Aquarium-safe silicone
  • Masking tape
  • Putty knife
  • Razor blade
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Instructions

  1. Instructions

    • 1

      Remove fish from your damaged aquarium and transfer them to a well-oxygenated temporary tank. Remove all accessories so the aquarium is bare.

    • 2

      Thoroughly dry the aquarium, locate the crack and then carefully align the glass so that both sides of the crack are flush with one another.

    • 3

      Tape one side of the crack with masking tape to hold the glass in place.

    • 4

      Apply a thick bead of aquarium-safe silicone to the un-taped side of the crack. Only use clear silicone sealants and always check to ensure that there are no mildew-inhibiting chemicals in the silicone mix, as they are toxic to fish. Most aquarium-safe sealants will clearly state that they are fish-friendly on the label.

    • 5

      Use the putty knife to help smooth the silicone over the crack to provide a solid seal and help stabilize the glass. Though it may not be aesthetically appealing, it is best to have a solid, thick seal on the tank to ensure that the crack does not reopen in the future.

    • 6

      Allow the silicone sealant to dry according to the recommended time on the instructions and then remove the tape on the opposite side of the crack and repeat the process.

    • 7

      Remove unwanted excess silicone by razor blade once dried.

    • 8

      Fill the repaired aquarium and ensure that the silicone seal is complete and that no further leaks develop before reassembling your fish tank.