Reseal a Glass Tank Aquarium




About: Zoo keeper

If your tank has to be resealed you may be intimidated to tackle it. Depending on the size of your tank replacing it with a new one can be very costly. If you need the tank ready in a day, resealing isn't an option. Make sure you give yourself time for it to dry so it can be done properly.

- Nice stable work space ( I used a space that I could let the tank sit for a few days,was at a comfortable height to work with and has decent ventilation for the fumes).

- Utility knife and a razor scraper

- vacuum

- rubbing alcohol and cloth

- disposable gloves

- tube of aquarium sealant ( do not purchase any with fungicide or any additive that can harm the tanks inhabitants).

- needle nose pliers


Step 1: Supplies

Here is a picture of the razors I used. I found myself using the scraper more than the other.

Step 2: Removing Old Sealant

I took my razor scraper and slid it underneath the old sealant and moved it down each corner of the tank.

Step 3: Onto the Other Side of the Seal

I went to the other side of the seal and did the same thing

Step 4: Pliers

Pliers came in handy to get into the corner pieces and remove what I couldn't with my hands

Step 5: Clean the Corners

I used rubbing alcohol and gauze to clean the area that I was going to apply the sealant to.

Step 6: Vacuum

This is important if you're resealing the bottom, make sure you get up all of the old sealant and dirt.

Step 7: Tape Up the Area

I used masking tape, but you can use painters tape as well. Give yourself a little space on either side of the joints so the sealant is not just in the corners of the tank.

Step 8: Add the Sealant

Apply the sealant to all the areas. On the sides of the tank I started from the bottom and brought the sealant up.

Step 9: Spread the Sealant

When you applied the sealant take your finger and run it down the freshly applied sealant so it flattens the bead you just put down. Remove the tape! Don't let it dry because your tape will be hard to remove.

Step 10: Let It Dry

For at least 24 hours.

Step 11: Test the Tank

I added a half tank at first, kept an eye on it for 24 hours, filled it up the rest of the way and tested another 24.

Step 12: Hurray



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    9 Discussions


    Reply 2 years ago

    Good point! Is it the sealant that's only good for 10 years or does something happen to the overall tank after 10 years?


    2 years ago

    I love the photo of the snake & turtle! The question I have is: Must I remove *all* of the old sealant? I want to repair an old 10 gallon. The bottom third doesn't leak. Can I leave the old sealant in the bottom?

    1 reply

    Reply 2 years ago

    Thank you, You just want to remove the excess thats flat on the glass. You dont want to get into the crevices like the actual glue that holds the corners of the tank together. To do that you would need a wire to slice through it. That really compromises the stability of the tank. This is for the bits you an get to. Take heed that a tank is really good for about 10 years and later it can weaken.
    Your question is that the top corners are leaking, and wondering if you can leave the bottom? If I were you I would do the whole thing. Look at it this way. If the top has already started to go, do you want to take the chance for the bottom ? It really isnt going to add that much more work or time and I would rather feel its all done then have to do it again.


    4 years ago on Introduction most pressing question after reading this Ible is "Are those turtle and snake really full time tank buddies??" I've never seen turtles and snakes housed together in a home aquarium set up before.

    Nice job with the sealant. That's what my mom used to do back when she had an aquarium business. Her personal tank went through a number of re-seals and lasted over 20yrs before she finally had to buy a new one!

    2 replies

    I replied and it didn't seem to post so I'll try again. The mud turtle and water snake have lived peacefully in their exhibit for several years. The turtle is too big for the snake to eat and both are fed well at my facility. It's a popular exhibit and I had to snap this pic of them nose to nose! It's so much cheaper to do your own repair than to buy a new tank


    Neat. The nose to nose is super cute, I just couldn't wrap my head around it! Snakes are one of few things I've never had.

    Great tutorial, no one likes having to replace a whole tank. Looks like the seal will hold for a nice long time! Welcome to instructables!