How to Repair Fish Tank: Leak and Crack Repairing Guide

A leaky aquarium is always a big problem. Most leaks start out as tiny drops. More serious problems can occur if the aquarium is not repaired. Of course, nobody wants such a situation to happen. So let’s try to explain how to fix the aquarium.

Before starting our article, if there is a big crack in your aquarium or there is too much water leakage, immediately take the living creatures in the aquarium to another place and take them to safety.

How to Repair a Cracked Fish Tank

If your aquarium has cracks, the best thing to do is to replace the piece of broken glass. For this, the aquarium must be emptied completely. If the bottom glass of your aquarium is cracked, check the surface on which the aquarium sits because glass can crack again after repair on an uneven surface.

We recommend that you start by wearing protective gloves and glasses

Take your fully drained and dried aquarium to a working area where you can work comfortably. To easily remove the silicone, heat it well with a hair dryer. Then cut the silicones of the broken glass with a utility knife. After separating the glass, thoroughly remove any remaining silicone from the aquarium glass.

Use a glass of the same thickness for repair

Make sure that the glass you replace is of the same thickness. Make sure that the edges are smooth before installing the new piece of glass. If necessary, smooth the edges with sandpaper. In this way, the silicone you will make will not tear in the future, it will last longer.

Glue the Glass

With paper tape, you can mask places where you don’t want too much silicone to stick. Place the aquarium with the area to be repaired facing up. Apply the silicone after making sure that the mating surfaces are clean and dust free. You can then glue the glass.

Fill the aquarium and check for leaks

After gluing the glass, remove the silicone that comes out of the aquarium. Then fix the glass with tape. You can now invert the aquarium and reapply the silicone to the interior. Fix it well after applying the silicone. The silicone dries after about 24 hours. Remove the tapes and check for leaks. If there is no leak, you can start using your aquarium.

Fish Tank Silicone Repair

Detect the water leak

If the leak is not clearly visible, observe any moisture on the glass. Look out for metal corners and silicon sticking out of the corners.

  • Move your finger from bottom to top without cutting your hand.
  • Find out where the humidification ends.
  • Mark the point where you detect or think wetness with a pencil.

Drain the aquarium water sufficiently

If the leak site is at the bottom of the aquarium, move aquarium creatures to another aquarium or a safe container. Provide a suitable environment for your fish as the silicone will have a drying time after repair. You may want to set up a quarantine aquarium for this.

Remove old silicone

You can use a knife or a similar tool. We recommend that you do the repair not only from the outside but also from the inside. Remember that acrylic glass scratches very easily.

Clean the area to be repaired with a fabric

You can wet the cloth with acetone, but make sure it does not mix into the aquarium water. Dry it with a paper napkin and let it dry completely for 15 minutes. You can shorten the drying time with a hairdryer.

Apply non-toxic silicone

Use material that is 100% silicone. Let it dry for at least 12 hours. If this period is 24 hours, better adhesion is achieved.

Fill the aquarium and check for leaks

If you have removed fish and other creatures from the aquarium, once you are sure the leak has been repaired, put them back into the aquarium. You can now enjoy your aquarium.

Consider Buying a New Fish Tank

If your fish tank is severely damaged and is leaking water, consider buying a new aquarium. A leaking aquarium is always a serious situation and can cause the aquarium to explode completely. While the full explosion of the aquarium can damage many items in your home or office, it is also very annoying. Consider buying a new aquarium without risking all this.


How to repair a water leakage aquarium?

Silicone repair is required in an aquarium leaking from glass joints. Aquarium silicone should be used for this. Fish can be poisoned if ordinary silicone is used. The aquarium is emptied completely. The old silicone in the leaking area is removed. New silicone is applied internally and externally. Leak control is made at the end of the drying period. If there is no leak, the aquarium can be reused.

The aquarium is leaking, what should I do?

If there is a silicone leak, the silicone should be repaired, and if there is a crack, the glass should be replaced. The same thickness of glass should be used for glass replacement. If the thinner glass is used, it may crack again and cannot withstand water pressure.

How to repair fish tank cracked glass?

Broken glass should be replaced with a glass of the same thickness. It is heated with the old silicone hairdryer. In this way, the silicone is easier to remove. It is cut with the old silicone utility knife. Silicone residues are completely cleaned. The edges of the new glass are well smoothed with fine sandpaper. The new glass is attached to the aquarium with silicon and taped at several points. In this way, the glass remains stable until the silicone dries.

The corner of the fish tank is cracked, why does the fish tank glass crack?

If the fish tank does not sit on level ground, the glass may crack due to the weight of the water in it. In order to prevent this, it is beneficial to lay a thin sponge under the fish tank while setting up.

Do Fish Tanks Crack Too Often?

Fish tanks do not crack easily and quickly if they are produced correctly. Users should also pay attention to certain conditions. A flat surface is essential for the fish tank. The fish tank should not be dropped while cleaning. If the basic rules are observed, you can use your fish tank for many years without any problems.

Do Fish Tanks Explode?

Although it is not common, the explosion of fish tanks can be encountered. The reasons for the explosion are generally using thin glass and placing a fish tank on uneven ground. Even if your fish tank has been produced correctly and placed on a flat surface, you should check your fish tank regularly. More water reduction than normal may indicate a water leak. If there is a water leak due to broken glass and it is not noticed for a long time, it may cause the aquarium to explode. Although the fish tank explosion has happened to very few people, it is an important issue to be aware of.

🐠𝙃𝙋 Team
🐠𝙃𝙋 Team
We're just like you - aquarium enthusiasts who love aquatic life! We've been caring for and breeding all sorts of freshwater and marine aquarium fishes, plants, and other pretty little creatures for years. We love sharing our knowledge with other fish hobbyists, and this article you have just finished reading is the best proof of that. You can read more about us here.

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