How to Fix a Leaking Aquarium Without Draining?

Last Updated on January 22, 2022 by Fabiola L.

Wondering how to fix a leaking aquarium without draining? These are the best instructions to solve this problem.

One of the major downsides to owning a glass fish tank is the likelihood of leaks. We believe that all aquarium hobbyists want to avoid this. The biggest problem is that this could lead to the breakdown of your entire aquarium or even worse to a large amount of water flooding your home.

If you notice any leaks, it is time to take action as soon as possible. How to fix a leaking aquarium without draining? Keep reading to find out.

Why Do Aquariums Leak?

Aquariums tend to leak when the sealant at the joints wears out or is damaged. The sealant is a layer of black substance that holds the glass panes of the aquarium glued together. It is usually weak, worn, or broken after a long period of use. As a result, leaks occur.

How To Determine If Your Aquarium Is Leaking?

It’s very simple; you just need to check the water level. You can mark the water level one day and then check to see if it remains unchanged the next day. Alternatively, you can wrap it in a paper towel. In this way, you can very quickly and efficiently determine the exact location where the sealant has worn out and is causing a leak.

How To Fix A Leaking Aquarium Without Draining

If you have found a leak location, it is time to talk about how to seal a fish tank with water in it. Well, let’s get to the point.

Remove Some Of The Water

To successfully repair a leak, you will need to remove some water. This is because this place must be well above the water level. By reducing the water, you will get a good insight into the matter and clean access to the leak site as well.

Remember, you don’t have to remove every drop, just one part of the water. First, put your aquatic pets in a safe replacement tank, so you don’t disturb them. Then remove all excess water with a cup but a bucket.

Scrape The Sealant

The sealant is what causes the leak in the aquarium. Accordingly, you need to fix it to solve the problem. Therefore, scraping is the best solution. This is where the blade scraper will help you the most. It is sharp enough to remove everything and gentle enough not to damage the glass.

Remember, you have to remove everything; otherwise, the leak will keep recurring. In addition, the old sealant and the new sealant do not stick together.

repair a leaking aquarium

Cleaning The Leaking Spot

Once you have scraped it off, it is time for a thorough cleaning. You can even apply a little acetone to a damp cloth and rub it on the leaking area. This will remove all debris and dirt.

Sealing The Leaking Spot

We have come to the most important part of this story – sealing. There are some things you need to pay attention to. Namely, it is necessary to use 100% silicon, and completely non-toxic silicon that does not contain any fungicides. Otherwise, you will only end up poisoning the water and fish in your aquarium.

Also, try to avoid applying silicone sealant to the outer surface of your aquarium. Solving problems from within is always more effective. For this part of the process, you need a sealing gun (to apply the silicone sealant), and a sealing tool (to smoothen out the silicon into a flat layer).

Lastly, don’t skimp on the material. The last thing you want to see is your fish nibbling the sealant.

Drying The Sealant

This step only requires your patience. As a general rule, silicon takes approximately 24 hours to dry completely. However, if circumstances allow, it would be best to leave the silicone sealant to dry for about 48 hours just to make sure it is completely dry.

In addition, you can even put a heat lamp nearby to speed up the drying process. If you really want to repair a leaking aquarium, you must allow the new sealant to dry properly; otherwise, it will not be effective.

Keep in mind that putting water back into your aquarium right away will only ruin the seal. It will immediately become soft under the influence of water and begin to peel. This will result in your lost time and effort.

Read more about How To Clean Aquarium Glass White Residue?

Returning The Water & Leak Check

We finally got to the last step – returning the water back to the aquarium. Gradually fill the tank with water to avoid putting pressure on the treated area.

Observe the situation for the next few hours. You can even do a paper towel test. If you do not notice a leak – congratulations, you have done the job!

How To Prevent Leaking?

There are a few things you can do to prevent this from happening.

    • Try to ensure that your aquarium sits on a flat surface.
    • The sealant, as well as aquarium age over time, and the problem, most often occurs after 7-10 years. Check the dates so you can reseal them.
    • Perform a silicone test by touching it with your fingernails. If you notice peeling, it is a sign that it is no longer good.

In Conclusion

A leaking tank calls for urgent intervention as it can cause a mini flood in your room and, or worse the loss of your aquarium pets. Aquarium seals are not lifelong; on the contrary, they lose their properties over time. Therefore, it is crucial to remove the old sealant and apply fresh to keep the tank impermeable.

Knowing how to fix an aquarium leak is not a science. Moreover, it is a fairly simple process that you can do in the comfort of your own home.

Do you have any tips and tricks for how to fix a leaking aquarium without draining? Let us know in the section below!

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