# Need help resealing a leaking tank



## Dewdrop (Nov 20, 2007)

My 29g. tank is leaking on the left side back seam that runs up and down the tank. I tried resealing just the leak with a black aquarium silicone that I had and it worked for a couple days. Then I bought some LOCKTITE clear silicone that says it's aquarium safe for tanks 30g. or less and not taller than 18". I should be safe here too but to me that sounds like it isn't that stong of a silicone so I'll return it and get the GE siliconeI recommended here.

I want to do it right this time and my questions are.....
Do I have to remove the plastic frame at the top and the bottom of the tank? Do I have to reseal both the inside and outside? Where do I start?

I was thinking I'd remove all the old silicone on the inside and reseal there without removeing the plastic frames unless the top frame will come off easily. Then only removing the outside silicone from the seam that's leaking and resealing it without taking off the frames. Will this work or will I have to reseal the whole outside too?

Can someone help me with where to start and end on putting on the silicone on the inside? Like do you go around the bottom first all 4 sides then go down the corner seams top to bottom or what?

Sorry this is so long. I just want to do it right...this time and know how to go about it before I start.


----------



## redstallion02 (Jan 17, 2008)

Sorry I can't help...

Just subscribing so I can see the answers. As I just tried to reseal a tank, three nights ago, and failed and would like to know the correct way as well.


----------



## Dewdrop (Nov 20, 2007)

ok redstallion02 :thumb: Maybe someone can tell us the CORRECT way to do it. I'd really like to get it done right this time too. Going now to put my fish, filter,water and heater in a plastic storage container. Guess I should check first to make sure the filter will hang on the side of the plastic container. I'd really hate to get everything in there and find out it won't :x . I'm already discusted enough :lol:


----------



## Mcdaphnia (Dec 16, 2003)

How old is the tank? Is it leaking at a spot where the inner silicone seal is worn away or peeling? When you use a single edge razor blade (in a holder for safety and for control) or a caulk devil to remove the inner seal without nicking the seal where the two pieces of glass are butted together, are the two pieces still holding together, or do they separate entirely if you gently press them apart?

Remove the rest of the inner (fillet) seal and test each butt seal as above. If all of the butt seals are tight even if leaky, you can clean the fillet seal residue away, clean with a paste of table (iodized or un-) and white vinegar or water, rinse clean, then clean with alcohol. Wear plastic gloves. The gloves are to keep the glass clean, not your hands. Invert the tank to dry. Dust won't fall in it inverted. Caulk the bottom seams with silicone 1 or equivalent brand, then immediately caulk the vertical seams, going from the bottom up. Smooth the new fillit seams with the back end of your caulk devil. Never use a finger tip to smooth the caulk. Oils in your skin will cause leaks. Also never use masking tape near the seams. The adhesive on it will bleed out under the silicone causing a future leak, plus it is easy to get bits of the tape permanently stuck under the silicone which looks very unprofessional.

What if the butt seals didn't pass the test? Tools you will need: Pick up a Windo-zipper and a caulk devil if you don't have them, and make a couple specialty tools. Take an old hack saw blade, a new one will do, and tighten it in a vise at about 30 degrees with only a fraction of an inch of blade sticking above the vise jaws. Hammer it over to a 90 degree bend. Now grind it into a chisel point sticking out on the side of the blade. don't leave much of the bend. Dip the other end in handle plastic or tape it. This tool is used to fish up on both sides of the plastic frame and cut any silicone holding the frame on. The chisel point scores any silicone on top of the glass so that it will tear when you carefully and evenly lift the frame away from the tank. If there is a lot of silicone under the plastic frame and the windo-zipper keeps hanging up, you will need to make the second special tool. Take a flexible metal putty knife about 1 to 1 and half inches wide and grind a chisel point on the end and about two inches of both sides, orienting all three the same way. When you use the tool, you will flip it over to cut the same area again at a slightly different spot parallel to the first. This prevents the tool hanging up in the silicone and sort of "chews" out any massive chunks that would be hard to remove with some other tool. Mark this tool with gradations like on a windo-zipper so you can see how far it is in. It is sharp enough to come up right through the plastic frame and cut it to shreds if you push it in too far. Once the frame is off, remove any now exposed bits of the inner fillet seal you hadn't remove earlier. Now use your single edge razor blade to nick the butt seals. Once two glass pieces opposite each other have been cut loose, the other two can be removed by bending them gently like opening a door. Now scrape and remove all silicone, clean as above, and reassemble using the plastic frames as jigs. Use the same caulking process as above and it will produce both the butt and fillit seals at the same time. Don't fiddle with any overage or drips of silicone. They clean up a lot better if given at least 48 hours to cure. Trying to wipe them up just makes more work for yourself.


----------



## Dewdrop (Nov 20, 2007)

Thanks Mcdaphnia. I don't know how old the tank is. I got it used (free off freecycle.com). I guess I won't know about the inner seal (this is where silicone is between the 2 pieces of glass or the butt, correct?)until I start taking off the old sealant. I'm going to have hubby read your directions tomorrow because I don't know anything about making those tools and kinda doubt he can make them either. I'm pretty sure he doesn't have anything to grind down metal.

Dang, I was really hoping I wouldn't have to take off the frame  . I can just imagine the whole thing falling apart when the frame comes off. Would it be ok to take off the frame at the top and redo the inside first, let that cure, then put the top frame back on and turn it upside down, take off the bottom frame then do the outside?

It's really late and I'm probably not thinking to clearly :lol: I'll sleep on it tonight and see what kind of answer I get tomorrow. I do have the fish, rocks,filter, heater, and most of the water out of the tank now. Still have to get the last of the water & gravel out and return this Locktite for GE silicone I without mold and mildew retardent. :thumb:


----------



## 12pointer (May 30, 2006)

Do what Mcdaphnia suggest! he knows what he's talking about.


----------



## Mcdaphnia (Dec 16, 2003)

The windo-zipper and the caulk devil are tools you can buy at many paint stores. They are made by this company.

http://www.reddevil.com/

The home-made tools might take your husband more time to make for fixing one tank, than taking extra time and having to go a little slower with the Red Devil tools might take. If he doesn't have a grinder and a vise, he isn't able to make them anyway.

If the whole tank falls apart when the frame is off, that is fine. As long as you can catch pieces of glass falling four different directions. I was sure that was going to happen with an old super heavy 150 gallon tank with very thick glass and silicone you could rip out by hand. I had my son and a couple of his friends standing around the tank, and sure enough, each one of them had a piece of glass to catch when the frame came off.

It would not be OK to keep the frame on one end. If the butt seals are gone, you want to take the tank apart to its components, clean off all old silicone, and completely rebuild it. The plastic frame does not add any support to the tank (except for the center brace on the top frame if it has one). It acts as a jig to align the parts correctly and hides the unsightly glass edges since the long edges have not been ground smooth like the short vertical edges that you can see. Oh, and watch out! Sometimes those "seamed" edges are still a little sharp in places.


----------



## Dewdrop (Nov 20, 2007)

Ok thank you so much Mcdaphnia, It was late when I read your last post and had me a little overwhelmed. I didn't realize I could buy the tools needed and was kinda flipping out because I knew we did't have a grinder :lol: I even understand the process now :lol: and can't thank you enough. I really appreciate your help :thumb: When I get everything together we need to do it, I'll be sure to post again if any problems or questions arise.


----------



## Razzo (Oct 17, 2007)

Good thread, I will be going through the same process with my leaking 125 gallon tank. Special thanks to Mcdaphnia for the advice you have already given.

Where do you guys biuy this GE Silicone I?

Thanks much!

Russ


----------



## Denny (Sep 27, 2008)

Suggestion: Lots of good glass shops could reseal the whole tank cheaper and labor wise as well. Might be worth looking into.


----------



## mepeterser2451 (Mar 23, 2007)

one suggestion, to take off the trim, use a block of wood and hammer. It won't crack and its much easier than it seems.


----------



## Mcdaphnia (Dec 16, 2003)

mepeterser2451 said:


> one suggestion, to take off the trim, use a block of wood and hammer. It won't crack and its much easier than it seems.


 I've seen that done. It often leaves divots of glass inside the frame. Usually nothing that would make the glass unusable, but you have to match it to fit back exactly so that the bumps inside the frame match back up to the scallops in the glass. I would rather take extra time and care at the beginning, rather than get slowed down later having to be sure every piece is reassembled in original order and having razor sharp fresh glass edges to avoid.


----------



## mepeterser2451 (Mar 23, 2007)

Mcdaphnia said:


> It often leaves divots of glass inside the frame.


i didnt have any problems like chipping the edges. It was actually still covered in quite a bit of silicone. First I loosened it by hand, detaching it at the sides, then after tapping it a couple times to get it loose, i pulled it off pretty easy. After scraping out all the silicone it fit flat on the edge. I had a bigger problem though with the razor blade because I kept digging into the glass accidentally and then I'd cut myself on the microscopic glass bits. dewdrop, you can check out mine at http://www.cichlid-forum.com/phpBB/view ... highlight=

I had to postpone finishing it till next summer cause I got sick all of a sudden. but some of the comments from others might be helpful for you too. good luck if you havent finished it already.


----------

