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Aquarium glue for happy fish

Aquarium silicone: Stop fish tank leaks instantly

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If you own an aquarium, you know what a mess a leaky fish tank can be. Fix it with aquarium silicone. It’s easy with our step-by-step instructions and tips for choosing the right materials.

What makes aquarium-safe silicone unique?

Millions of people love the beauty of an aquarium filled with colorful fish. What do you do, though, if it begins to leak? Fix it with aquarium sealant! This isn’t a difficult repair, and doing it yourself can save you a lot of money.

You must be sure to use an aquarium glue that will hold up under water, generally silicone or an epoxy. The other concern is for the health of your fish. Choose a fish-safe silicone or epoxy so that no harmful chemicals are released into the water.

Aquarium-safe silicones:

  • are safe to use with both freshwater and saltwater
  • will hold up to continuous submersion inside the tank
  • are non-toxic to fish and other aquatic life

Aquarium-safe silicone: Step-by-step application

To repair your fish tank, step one is of course to drain it and allow it to dry. (If the leak is near the top of the tank, it may be possible to drain it to a point below the leak and repair it.) Once you’re ready, follow these steps:

  1. Remove as much of the old sealant as possible in the area being repaired. Use a razor or sharp-edged scraper to loosen and remove it. Avoid dropping the shavings into the water if the fish are still in the tank. (If the tank is empty, it is recommended that you check all the seams to ensure that they are not loose.)
  2. Clean the joints and surrounding areas of stubborn residue and dirt or impurities.
  3. Apply a bead of aquarium silicone to the inside of each seam being repaired. Make sure that there are no gaps and that each bead of sealant is continuous.
  4. Smooth out the bead with a caulking tool or a moistened fingertip.
  5. Apply an even bead of the aquarium sealant to the exterior side of each seam and then smooth it out.
  6. Allow for the aquarium-safe glue to fully dry before refilling the tank. (See the manufacturer’s suggestions.)
  7. When you refill the tank, do it slowly so that any leaks will be evident immediately.

Choosing the best fish tank silicone

Loctite Clear Silicone is an excellent choice for repairing aquariums and many other areas around the home that are subject to moisture. It forms a strong, waterproof seal and will adhere to metal, glass, rubber, and tile. This silicone is safe for both freshwater and saltwater aquariums. It won’t crack, peel, or shrink, and it stays flexible enough to prevent leaks from vibration or temperature change.

For quick fixes that will hold up well under water, try Loctite Epoxy Marine. The two-part epoxy liquid will produce a rigid, high-strength bond in about 2 hours. It cures to a white finish and can be applied and will cure underwater. This adhesive bonds to glass, metal, concrete, fiberglass, most plastics, and many other materials. The convenient dual syringe makes applying this fish tank glue very easy.

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