Repairing a 265 gallon glass tank...

  • We are currently upgrading MFK. thanks! -neo

TheFishGuy

Candiru
MFK Member
May 8, 2006
785
6
48
51
North east Ohio
www.monsterfishrescue.com
Monster Fish Rescue got this tank as a donation a few months back and now that the weather has broke it's time to get it repaired. The tank is 84"x30"x24" tall:
Front
001.jpg


Back
002.jpg


The plan is to go right over the back pane of glass with a sheet of hardie pannel coated with four coats of drylok then siliconed into place... Then after the tank holds water it'll be connected to my 240 via a 6" waterbridge made from clear pvc:
047-1.jpg


I've got everything to do the reapair and i like to take lots of pictures, so if this works maybe other can use this inexpensive method of tank repair on any size tank :)
 
If you cant afford or are unwilling to replace the back glass then I would just patch it with more glass from within. Several pieces simply laid side by side over the back panel as a patch will be easy and cheap to do. It doesnt need to be a single panel.

If it were a smaller tank some sheets of slate would do and also make a nice background. I have patched with both slate and glass before.
 
I didnt realise you already had the materials. Still I would be worried about the bond between silicone and drylock/Hardiepanel and even if it was waterproof I would be forever worried about when it may fail in the future. Google seems to have instances of this happening whilst I would be very confident with a silicon - glass seal. I have no experience with Drylock however so dont mind me. I wish you luck.
 
Don't worry fish dance, GE silicone I and drylok seem to be made for each other LOL I've done a few projects with them!

Ok, I’ve got an Update:

As some of you may know I’ve started threads about this repair on a bunch of forums across the net. I decided to do this for a couple of reasons. The first is to possibly give people another way to repair tanks, large or small. The second reason is to hopefully meet a few more people that live in the fish world! On a lot of sites I’m known as “monsterfishrescue” or “TheFishGuy”. My real world name is Jonathan… Nice to meet you!
I’ve decided to make updates on all the sites the same to save me some time typing this up over and over again… Lazy, I know… LOL
Ok, I’ll get to the point. We got rained out this afternoon so I decided to take some time with this tank. I’ll take you all through what I did this afternoon step by step. Hopefully that’ll be the easiest and most clear way to get an idea of what’s involved and what exactly I did!

Ok, here’s the Drylok for those of you that don’t know what it is or what it looks like. This is the water based version of the product, it’s a basement water sealer that so far has proved to work great for aquarium projects:
http://i47.photobucket.com/albums/f197/jstraz/265 gallon/001-1.jpg

This is the Hardie Panel, This IS NOT hardie backer board for behind ceramic tile. This is another product made by James Hardie to be used as soffits on houses sided with Hardie plank siding. It’s 5/16” thick and it’s a 4’x8’ sheet. It is concrete board and can be special ordered at any lumber yard, Lowes or Home Depot for about $30 a sheet:
http://i47.photobucket.com/albums/f197/jstraz/265 gallon/002-1.jpg

1.) The first thing I did was measure how big the panel had to be. I measured the tanks back wall and took off ¼” for breathing room. Since the Drylok lays on quite thick you’ll need some extra room.

2.) Next I cut the Hardie panel to 23 3/8” x 82 ¼”
http://i47.photobucket.com/albums/f197/jstraz/265 gallon/003-1.jpg

3.) Then I tried to put it in the tank laying flat but it didn’t fit, glitch number one in todays project. We’ve got a saying at work that goes something like this. “There are no problems, just opportunities” So now I had the opportunity to break some glass! Ye ha!
http://i47.photobucket.com/albums/f197/jstraz/265 gallon/004.jpg

4.) It seems as if the top braces were made from tempered glass, which explodes when you break it or try to cut it! LOL I also had to drill out the rivets that held the aluminum braces in and pry it off. No big deal really…
http://i47.photobucket.com/albums/f197/jstraz/265 gallon/005.jpg
http://i47.photobucket.com/albums/f197/jstraz/265 gallon/006.jpg

5.) It’s a perfect fit! (measure twice cut 16 times LOL)
007.jpg


But not without some damage. As I was standing the Hardie panel up inside the tank my knuckle rubbed on the back pane of glass on the tank. The tank won LOL
http://i47.photobucket.com/albums/f197/jstraz/265 gallon/009.jpg

Nothing a little piece of cloth and some electrical tape can’t handle LOL
http://i47.photobucket.com/albums/f197/jstraz/265 gallon/010.jpg

6.) With the piece cut and ready to go I was able to get the first coat of drylok on it. I painted about a 4” swath on the back side around the edges and two stripes somewhere in the middle. Now that I think about it I’ll probably paint the entire back with the next three coats to ensure that the silicone will stick to the back .
I finished this first coat at 2:11 pm eastern standard time so the next coat will go on at 6:00 this evening. Then a third coat at 10:00. And if I can drag myself out of bed tomorrow morning I’ll get the fourth coat on.
http://i47.photobucket.com/albums/f197/jstraz/265 gallon/011.jpg
http://i47.photobucket.com/albums/f197/jstraz/265 gallon/012.jpg
013.jpg



Since I’ll need the roller again in a couple hours I loaded the roller with drylok and rolled it into a plastic grocery bag to keep it from drying.
014.jpg


7.) With the first coat on and drying it gave me an opportunity to clean the tanks back pane of glass and clear the edges or excess silicone. I also removed a few of the other loose pieces of glass from the back so they wouldn’t become an issue later. I did end up using a couple of razor blades to clean the entire back of the tank. When it comes time a week from now the entire back will be cleaned with glass cleaner and acetone to make sure the silicone sticks!
http://i47.photobucket.com/albums/f197/jstraz/265 gallon/015.jpg
http://i47.photobucket.com/albums/f197/jstraz/265 gallon/016.jpg


Total time invested so far:

1.5 hours

Total money involved: $142.00

Tank: $0.00
Two tubes of silicone and one gallon of Drylok: $30.00
Hardie panel: $0.00
Three tubes of silicone already in stock $12.00
Water bridge (clear pvc and 90* fittings) $100

Questions or comments are always welcome!
 
Ok, I’ve got an Update:

The piece of hardie panel went in well, it fit good! I’m feeling rather confident about this one 


After cleaning the glass with acetone (which I feel is key to a great seal) I cut a bunch of prop sticks to hold the hardie in place.

001-2.jpg


002-2.jpg


After that I siliconed the edges with a heavy bead and I also went over every crack in the glass. Beyond that I made circles out of the silicone to hold the hardie in place. Making circles is a trick I learned from mirror installers. It creates a vacuum and you actually hear the silicone “fart” as it’s pushed into place LOL

003-2.jpg


After the prop sticks were put in place pushing the hardie tight I ran a nice bead of silicone around the inside corners then smoothed it out with the back side of a spoon. That pushes any unwanted bubbles out of the silicone making for a tight seal.

004-1.jpg


005-1.jpg


Tomorrow when I get home from work I’ll have the task of moving the tank next to my driveway to fill it with some green nasty pool water to see if it holds. Others will say 24 hours isn’t enough…. I disagree  (plus I’m impatient LOL)

Wish me luck!

Here’s more pics!

http://i47.photobucket.com/albums/f197/jstraz/265 gallon/006-1.jpg

http://i47.photobucket.com/albums/f197/jstraz/265 gallon/008.jpg

http://i47.photobucket.com/albums/f197/jstraz/265 gallon/009-1.jpg
 
MonsterFishKeepers.com