How to Fix a Cracked Aquarium

A cracked aquarium can be costly. Aquariums can be expensive to replace, particularly large ones. And aquariums of all sizes can cause expensive water damage to your walls and carpet. Additionally, your pets' lives are on the line when making such a repair. Such a repair can be difficult, but if done properly, you can save your tank and your pets.

Things You'll Need

  • Five-gallon bucket(s)
  • Air pump/airstones
  • Rubbing alcohol
  • Aquarium glue
  • Disposable rubber or latex gloves
  • Popsicle stick
  • Razor blade
  • Replacement aquarium glass
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Instructions

    • 1

      Evaluate the situation. You should ask yourself several questions. First, would it be cheaper or easier to replace the aquarium? Is it under warranty? Would your fish survive the two days or so it takes for aquarium glue to dry? Where is the crack on the aquarium? A crack on the bottom could be a lost cause.

    • 2

      Place your aquarium inhabitants in buckets. Add aeration with airstones. Hardy freshwater fish can survive several days like this. Delicate corals might not survive the repairs.

    • 3

      Drain the aquarium. Clean the area around the crack with rubbing alcohol.

    • 4

      If the crack is near the top of the aquarium, and the integrity is not compromised, glue the crack itself. To do this, apply a line of aquarium glue along the crack directly from the bottle. Then, run the Popsicle stick along the glue to smooth it down. Allow time to dry -- typically two days or so.

    • 5

      If the crack is more severe, gently pry off the aquarium frame. Slice the aquarium glue off with razor blades to remove the damaged pane. Take care not to put pressure on the damaged pane, as it will shatter.

    • 6

      Clean the remaining aquarium glue from the surviving panes with a razor blade. The joint must be clean for the replacement glass.

    • 7

      Order a replacement pane for the aquarium. Many hardware stores and picture frame stores can cut glass precisely, while you wait. Make sure the glass has the same dimensions and thickness as your original pane.

    • 8

      Hold the new frame in place with duct tape, as securely as possible. Now, create a line of aquarium glue along the seams, and flatten it either with a gloved finger or a Popsicle stick.

    • 9

      Allow aquarium glue one to two days to dry, per the manufacturer's instructions. Then, remove any tape. Gently work the top frame back into place.

    • 10

      Leak-test the aquarium; filling it with water, marking the waterline with a marker, then covering the tank, If the waterline remains constant for at least 24 hours, the repair was successful. If not, the tank may be a lost cause.