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resealing tanks

danger_chicken

Swim Fishy Swim!
Does anyone have a good link on how to reseal a tank or give me detailed directions? Thanks. I've got a 180 that needs it.
 

DiscusnAfricans

Past President
I'm just going of what I can remember, but someone recommended removing all the old silicone with a razor blade and resealing the entire tank. They said it was too much trouble to try and "spot seal" plus you'd probably spring more leaks in the future. Use aquarium specific sealant, and be liberal with application. You can always trim excess later, or just cover it with substrate if the bottom joints are messy. I know I'm not anything close to an expert, just putting out my opinion. Good luck
 

lonlangione

Members
I have fixed many large tanks in my day. Here are quick step by step instructions.

1.) Be sure the tank is leaking and it is not a canister filter or something else causing capillary action.
2.) How old is the tank? Look at the side edges of the tank. The area where the front glass meets the side piece of glass should be clear and free of air bubbles or "white" areas. If the sides are white, it would be prudent to re-seal the whole tank.
3.) Determin where the tank is leaking. If it is a side piece you are lucky. If it is the bottom. Get a case of beer before you start.
4.) If it is the side, the first thing you have to do is get the plastic frame off the tank. If it is an Oceanic tank this can be a real b**ch.
The best way to remove the frame is to take a putty knife and carefully work the putty knife up the outside of the frame and work it back and forth. DO NOT TRY TO PRY THE FRAME OFF. You stand the chance of cracking the tank. While you are doing this with the frams, keep "rocking" it back and forth with your hand.
5.) Once you get the frame loose, take a piece of furring strip or some type of wood and wedge it in to hold the frame away from the top and bottom of the glass side piece. Do this with the bottom frame as well. (putting the tank on a table with about 2' - 3' of it hanging over the edge helps)
A SHORT CUT: You can take a hacksaw and cut the frame piece in the corners on an angle and the remove just the side pieces.)
6.) Once you have the frames away from the side piece, Take a brand new single egde razorblade and work in into the seam from the outside. BE VERY CAREFUL, you still want to be able to pick your nose with your fingers when you are done. Do this starting at the top on both sides. You can cut away the interior silicone to help with this process. As you stick the single edged razor blade into the seam, use a pair of pliers to pull it out. Keep working the razor blade to whole way down both sides. With a tank this size, you can pull on the glass slightly to help it along.
7.) Once you have the sides loose, cut all of the excess silicone away on the bottom. Then slightly pull the piece of glass outward while running the razor blade on the inside. The side piece will eventually come loose.
8.) Take the side piece and using another single edge razor blade clean off all of the old silicone. Do the same for the front, back and bottom pieces. You can get the old silicone off with the razor blade. Some people will tell you, paint thinner, naptha, lighter fluid, alcohol (all types), etc. But none of these will "cut" the silicone. There is a silicone remover available from this company http://www.rpm-technology.com/Digesil/Digesil.htm. I have never used it and I don't intend to start. Single edged razor blades work fine.
9.) Once all of the old silicone is removed you are now ready to re-seal the piece in place. This part will be the most controversial part of this whole dissertation. Go to an Ace Hardware and buy a tube of clear 100% silicone. It's like $5.99 for a caulking tube. This is 100% silicone, nothing else. I use at least 2 cases of this stuff a year. I buy it on sale for like $3.99 and keep it till I need it. There are literally 1,000's of different silicone sealants on the market that have all kinds of stuff in it for one reason or another. Again, this is 100% silcone. I don't give a rats a** what anyone tells you, this is fine to use.
10.) You should have some duct tape at this point as well. Put a medium size bead of silicone on the bottom and side of the tank. Once you have done this put a bead of silicone on the bottom of the side piece. Now sit it in place from the outside in. Move the top of the piece in so it is flush on the outside. Tape it securely at the top of each side with the duct tape. Now take your finger and go around the inside of the tank and smooth out the silicone. If it come out the outside of the tank that is great. Just leave it alone and let it dry. You can cut the excess off easier than you can clean in off. Now look at the front and back edges of the tank. Be sure there are no air bubbles. If there are, just take a glob of silicone and put it on your finger and push it out from the inside.
11.) Let the tank sit for at least 5 days so the silicone can cure.

IF IT IS THE BOTTOM THE TANK IS LEAKING FROM:
1. Take of the whole bottom frame.
2. If you are lucky the sides are siliconed to the base and the base isn't up inside the tank. If the bottom is up inside the tank, get two cases of beer.
3. This is a nightmare to fix. You just have to have lots of patience to cut it lose. Or you can clean off all of the silicone on the inside bottom of the tank, have a new piece of glass cut to size and silicone it in place over the old one. But this can be very expensive and it adds a tremendous amount of weight to your tank.

Take your time while doing this. And one last thing. You can not get away with just cleaning the silicone off the inside and putting new on. The way slicone works is in bonds together at the seams. Hence a clear looking seal is fine, a cloudy white seal is failing. If a seal is broken and you put new silicone on the interior, it will rip in a few months or even weeks. You can do this with 5 1/2's and 10's, but not a 180.
Hope this helps, Lonny
 
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DiscusnAfricans

Past President
Again, this is 100% silcone. I don't give a rats a** what anyone tells you, this is fine to use.

I guess you can ignore my comments. I think Lonny went into a little more detail. Great instructions, my problem is my patience shrinks with every beer I drink. I'd never make it through this process but I'm sure it works. Good luck!
 

Spine

Members
Great instructions Lonny. Now all you need is a couple pictures to go with it and you have a article for the Biotope.
 

Lively

Members
I did a 10 gallon, it will take more than beer for me to ever do anything larger. I broke the trim after spending hours trying to gently pry it off.

A couple of thing's I'd add to lonny's very good instructions - be sure to get the kind of silicone that doesn't have anti whatever stuff in it. And, it stinks a lot, a whole lot when you caulk - do it outside if you can.

And, a link to frames if you break yours when you remove it.

http://cciaquarium.com/index.html

Finally - good luck...
 
Good luck Danger. I have never resealed a tank. The one my dad did when I still lived with them spring a leak and when I came home it was coming out like a water fountain on the floor. lol
 

cabinetmkr39

DavidG / CCA Member
If your going to put your finger in the silicon to smooth, Drip your finger in some Denatured Alcohol first it helps smoothing with out sticking to your finger. Just my 2 cents.
good luck
 

danger_chicken

Swim Fishy Swim!
Thanks Lonny!

And one last thing. You can not get away with just cleaning the silicone off the inside and putting new on. You can do this with 5 1/2's and 10's, but not a 180.
Hope this helps, Lonny
You just broke my heart.
It is the bottom but I'm not home to see if the bottom is on the inside. The silicon on the sides on the inside looks weak, can that be replaced without completely tearing the tank down? I think the seams on the sides are ok, but I'll take a closer look tonight.
 

SubMariner

Master Jedi & Past VP
Michael, my suggestion would be to Youtube it. That's right Youtube it!

There are hundreds of instructional videos on there to your disposal.

Good Luck,



Richard
 

Frank Cowherd

Global Moderators
Staff member
Here is a trick that works for any size tank and on the bottom or on the side, but it may not result in a pretty tank particularly if you have to do it on the front side.

Anyway, identify where the leak is. IF it is not obvious, dry the outside of the full tank and then place a paper towel over the area. Where the wet spot shows up is where the leak originates.
Then empty the tank, clean it out where the leak is with a razer blade. Wet a paper towel with acetone or isopropanol (rubbing alcohol) and rub down the area to both dry and remove any oils. Then use a blow dryer to dry the area even into the leak.

Then get a long piece of glass or Plexiglas that is longer than the area , about one inch on either side of the leaking area. This piece can be as small as a half an inch wide or as wide as you want. Lay down a generous bead of silicon glue , use the best you have, the 100 % stuff is best. push the piece of glass or Plexiglas into the glue and hard against the leaking area. If the leaking area is really large the wider the piece of glass or Plexiglas is the better because it will not break when you are pushing it into place. You can actually redo all of the seals in an old aquarium in this manner if all you want is a tank that holds water.
 
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danger_chicken

Swim Fishy Swim!
I'm afraid, very afraid! I'm considering breaking the tank down and using the glass for a plywood tank. I know I can work with wood, but that much sealant and patience...I don't know.

Anyone want to $eal it for me?
 

lonlangione

Members
You bring the tank to Dover, PA and I'll re-do the whole thing for you. $150.00 + cost of silicone.

Lonny

It was mentioned to use plexiglass to fix a tank. It has been my experience that silicone does not bond with plexiglass.
 

danger_chicken

Swim Fishy Swim!
If you were able to do it at my house I'd go for it. But getting a truck and the people together to move up there is too difficult.

Turns out this was a "semi" false alarm. The tank is NOT leaking. The window tint that was used as a background had an air bubble in it that looked and acted like water was pooling. When I stripped the tint off, the glass was completely dry. That section had been submerged over night. Using Lonny's description I checked the silicone. The glass on the bottom is the base and the silicone is good. The corners were another story. No leaks but spots had algea behind it so I stripped it and didn't take much at all to get it off. Soo, I'm committed now.

Lonny - Thanks again for the walk-through!
 

George

CCA Charter Member and person in charge of the we
It was mentioned to use plexiglass to fix a tank. It has been my experience that silicone does not bond with plexiglass.
We finally agree on something 100%. silicone will not bond with Acrylic or Lexan which seem to be generically called plexiglass but are very different.

George
 

Lively

Members
You can bond glass to stone with silicone. One of these days, I'm going to make my slate bottom tank that way.
 

kbeaudean

Members
Great information!! I am getting ready to redo my 55 that sprung a leak! Had to hurry and move a bunch of fish!! Thank goodness for hard wood floors!!
 

George

CCA Charter Member and person in charge of the we
You can bond glass to stone with silicone. One of these days, I'm going to make my slate bottom tank that way.
You may find that this bond is really only temporary, especially under water. Rock is porous and will bond temporarily with almost anything. The problem is that it is almost always semi-soluble. Eventually the bond will likely let go.

I wouldn't try a slate bottom for several reasons. The least of which is simply WHY would you?

George
 

Lively

Members
I guess I'll have to look around for that black stuff or do a long trial with the rock.

When I was tested the theory, I wasn't going to build a fish room for awhile. Since I'd have barebottom tanks in the main house, slate bottom tanks would look more interesting. Planning a fish room now, but still want to make one. Now the reason is because I didn't get to finish what I started... I hate that.
 
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