Tank Leak

[Mihai]

Hi there, I have a problem with a strange tank leak. The tank is a 35 gal hex tank that I got a long time ago (about 5 years ago) from Wade. For five years all was fine until around last Thanksgiving (2008) when, late evening (11pm) it just started to leak big time. I mean, from a vertical seam about 1/3 up there was a jet of water shooting about 20" onto a nearby couch. Luckily I heard it from the nearby room (was making a bit of a splash), so I was able to empty most of the water in the toilet and not on the couch. I emptied the tank completely, stripped down all silicon on all sides, re-did all sides (now it looked really nice!), then put it up together again and it held great... until yesterday evening. Yesterday evening (earlier now, 9:30pm or so) it started leaking again, in the same spectacular manner (splashing to the same couch). Needless to say that nobody was in the room at either leaks, so nobody did anything to the fish tank. I thought that I did a good job with the repair - it looked so nice, but it obviously was not enough - somehow the water managed to get behind "my" silicone and found the same tiny hole between the two vertical panes that found the first time around.

I'm at a loss - I'd like to fix it if I can, but I'm not sure what can I do more than I did - maybe only if I also clean the bottom and top and remove the glass panes and put silicon between the two glass panes, but this sounds like a headache (I'm not even sure how to remove the panes without breaking them). I know that I read on the Internet a bit before doing the fix and several sites said to do pretty much what I did: strip the old silicon out, clean with vinegar (well!), then put new silicon in (use masking tape to get neat lines).

I'm about to go order a new one, but I'm open to any suggestions that may lead to fixing this one...

Thanks,
Mihai

 

[Anonymous]

How level is the floor/stand? Perhaps it's off enough it is putting a strain on that one point...

other than that I got nuttin'

 

[Len]

Does all the sides align properly? If it fails in the same way, I have a hunch the tank is a bit misaligned somehow and will eventually lead to another failure (same stress applied over time).

 

[Mihai]

You may be onto something - I think that this is the only tank that I setup without the usual foam cushion because it has a wooden base that holds it - the base sits on a wooden table that sits on a hardwood floor. Needless to say that either the floor, table or base can be slightly warped - I'm not even sure how to check for that - a level would never show such a small imperfection (it's nothing really visible). The tank looks in good shape, all seems in alignment...

So what are you saying - should I try to fix it again, and try with a foam cushion inside the base?

M.

 

[iseeweed]

Interesting... Silicone is a very strong bond to glass if applied properly. I guess my only suggestion would be to strip it down and clean the glass with acetone or a ketone(MEK), to make sure there is no contamination on the glass surface. What brand of silicone did you use to repair the leak? I once built a tank from scratch(37 tall) and used All-Glass silicone with no issues.
Question, are the glass edges polished(small taper on the edges) or a straight break? Do you know if the glass is tempered?

 

[Mihai]

I think I used "Perfecto" aquarium silicon from Petsmart - I didn't realize that there is a difference in quality. Also, I'm not sure if I used acetone - maybe I did, but I think I used vinegar - maybe that's why it didn't work as well as it should have... I'll give it another try with
- acetone
- all glass
- foam under the tank (at least a little bit)

Thanks for the ideas,
M.

 

[Mihai]

Question, are the glass edges polished(small taper on the edges) or a straight break?

Hmmm... the tank is a hex tank, so the glass is not cut at 90 degrees, but rather at 60 or so. As such, they do come down to a narrow edge (which is chipped here and there, but not too bad). Actually, about 1" under the leak there is a small chip in both panes (at the exterior), but that's not where it leaks from - it leaks 1" higher up through a narrow channel between the two glass panes (the channel is about 2mm ~ 1/8" wide). Because the leak was so strong I could pinpoint exactly where it leaked.

Do you know if the glass is tempered?

I have no idea - how do I check and why does it matter? I think that the tank is a "stock" all glass tank, I don't think it has anything special...

Thanks for the help,
M.

 

[iseeweed]

Yeh, I don't really think it makes a difference if the glass is tempered or not, just curious. I'm not sure about the quality of silicone, I think as long as it is 100% without any mold inhibiting stuff like the bathroom caulk, you should be fine. Just make sure you clean it well. I once tried to remove a pane from an all glass tank and was unsuccessful.

 

[Anonymous]

If it were me, and I'm a DIY nut, I would give the tank away to someone else who wants to fix it and just buy a new one (maybe someone wants a reptile tank). I've made a few tanks - some glass, some acrylic. I wouldn't bother myself with a rebuild though unless it was a sizeable, expensive tank. Removing the old silicone is a PITA. It's going to take a lot more than just an acetone wipe. Razor blades, buffing wheels, heavy scrubbing, scraped knuckles, and explitives are what I'm picturing.

I would imagine the tank was racked putting stress on the seam.

The silicone you used was fine.

 

[Mihai]

I was pretty much on the fence on this, and you're pulling me down. Last time I fixed it it wasn't too bad, but it didn't end up good either . I did scrape it with a blade pretty well, then used vinegar and it *looked* really clean. Was it really clean? Not sure...

M.

 

[Anonymous]

Use isopropyl alcohol here, not vinegar. Feel it with your finger, and finally use something with some 'grip' (plastic scrubby pad) to really nail those lingering bits of silicone.

If that bottom plate is flexing, get another piece of glass and silicone it directly underneath for added rigidity.