Is this the end?

[esoxlucius]

This is scary. The bottom strip of bracing running the full length of my 6x2x2 has developed a "puddle" of water under it, and it is slowly creeping, getting worse. There must be a pinhole sized hole developed in the silicone somewhere. It's difficult to explain but the picture below will give you an idea what's happening. You can clearly see the dark shadow. Also, my diagram shows you where the pinhole is more likely to be.

There's no external leak, not as much as a drip....yet! So I'm guessing that the silicone holding the actual outer panes together is sound. I don't know what the other side is like because I have decor/gravel covering up about 90% of that bracing strip.

The tank water may very well "flood" the whole strip eventually, and still be fine as long as the main silicone is ok. But then again, this could be the beginning of the end of this tank, which is only 6 years old. What do you reckon?

 

[robmcd]

That is a bit unsettling!! I would hate to see a blowout on those hardwood floors ?

 

[Sticky90]

My friends 70 bow front had this and when he drained it to reseal he found out it was the bottom panel starting to let go. It was the end of that tank. Drain and inspect, I wouldn’t wait

 

[Chub_by]

If I were you I would drain that asap

 

[jjohnwm]

That is strange. If that is water creeping in between the pieces it looks as though the source is a pinhole somewhere along the seam between the brace and the vertical front pane, since the dark area does not appear to reach the other side of the brace at any point. Maybe the brace was glued in after the structural silicone holding the top and front together had dried, and so the new silicone wasn't able to bind with the old?

Are you certain that is water in there? It's hard to imagine why water would force apart the brace and the bottom like that even if it could contact the seam. The entire rear edge of that brace has been constantly exposed to water for years, and yet there is no indication that it is entering along that side. Defective silicone? Was the brace added after the tank was completed? For that matter, do you know if the brace is actually required? Maybe research what thickness of glass is needed for that size and depth of tank. If the glass is thick enough then the tank might be just fine without bottom bracing.

If worse comes to worst and you determine that the brace is required, you could carefully cut the silicone holding the brace in place and remove it. Remove all traces of silicone from the interior surfaces of the front and bottom, without cutting into the structural silicone between the panes. You'd need to clean off all the interior beads in the tank to ensure a proper continuous seal; if you have ever resealed a tank yourself this is exactly the same preparation. Then reseal the entire interior of the tank, and at the same time glue in a new brace. This would have to be done all at once so all the new silicone is a continuous waterproof seal, completely covering the old structural stuff everywhere in the tank.

I wish I could be more helpful, but I have never seen this condition before. The repair I am suggesting is a tedious PITA, but it will correct the issue and save the tank. Keep us posted, and good luck!

 

[jjohnwm]

just thought of an easier fix, although perhaps more visible. Leave that brace alone. It functions to increase the contact area along the bottom seam, giving a stronger adhesion between the pieces of glass. If it is letting go, then you have lost the benefit of that increased silicone contact surface. But you can add another brace along the bottom on the outside of the tank. A piece of thick glass the length of the tank and a couple inches wide can be siliconed lengthwise along the exterior of the bottom seam, so that it is adhered to the front panel and the front edge of the bottom panel. This is a relatively simple fix , requiring only that the glass outer surface be properly cleaned. You could probably do it without even taking out the fish. Just remove about 2/3 of the water to relieve pressure, silicone on the piece and clamp it firmly till it cures. Done carefully it shouldn't look too bad and it will be strong.

If you try this I would suggest doing both the front and rear bottom seams. Whatever is causing the issue in front was probably done the same way at the back. Better safe than sorry.

 

[..puSkar..]

just thought of an easier fix, although perhaps more visible. Leave that brace alone. It functions to increase the contact area along the bottom seam, giving a stronger adhesion between the pieces of glass. If it is letting go, then you have lost the benefit of that increased silicone contact surface. But you can add another brace along the bottom on the outside of the tank. A piece of thick glass the length of the tank and a couple inches wide can be siliconed lengthwise along the exterior of the bottom seam, so that it is adhered to the front panel and the front edge of the bottom panel. This is a relatively simple fix , requiring only that the glass outer surface be properly cleaned. You could probably do it without even taking out the fish. Just remove about 2/3 of the water to relieve pressure, silicone on the piece and clamp it firmly till it cures. Done carefully it shouldn't look too bad and it will be strong.

If you try this I would suggest doing both the front and rear bottom seams. Whatever is causing the issue in front was probably done the same way at the back. Better safe than sorry.

Agreed . What you need is a thick glass waterproof bandaid.
And if the glass used in construction of the tank is 12mm or more you're safe.

 

[esoxlucius]

Thanks for the input guys. This is any aquarists worse nightmare. Although scary looking that tank could last for years and years with no issues...or I could get a call off my wife later today saying we've got 180g of water on the floor!

My decisions made, that tank is going, no messing, no botching, it's going. I have to expect the worse, and soon, so I need to act quickly.

I'm going to be busy over the next few days, I'll keep this thread alive with any progress.

I love tinkering and building new stuff and getting into new projects, but not when there's a ticking time bomb running, lol.

 

[esoxlucius]

Well, a bit of an update, and many of you may think I've gone mad. I went to see the tank builder yesterday. I spent 2 hours with him in his workshop, which is at the back of the LFS.

I showed him several pictures and aired my concerns and he was extremely surprised!! Not by the fact that I've got pooling going on under the bottom brace, no. The only thing he was surprised about was that the pooling has taken 6 years to start showing! In his 35 years time in tank building he said if pooling is going to happen it happens much quicker than that. He went onto explain.

He told me there are three critical areas of tank building. Glass thickness, the seal, and bracing (on big tanks). Once you have established correct glass thickness for the build then the seal is the next most important area. The 6 panels need to be perfectly put together, and he assured me that the 6 panels on my 180 will be sound for many many more years than its current age of 6.

The bracing, if needed, is put on afterwards. By which time the tank is already perfectly sealed anyway. The bracing is nothing to do with the seal, it's just to give a bit more structural integrity. And due to the brace not having much to do with the seal, when he attaches the brace he secures it in place with silicone, but doesn't spend ages and ages "thumbing" the silicone to perfection. So it's feasible that "pinholes" are quite common in this area. That is why he was very surprised it had taken 6 years for pooling to begin.

The more he talked the less concerned I became. And at the end he said if I wanted he'd start another 180 for me, but he was absolutely unequivocal in his opinion that my tank was fine. He said I'd just be wasting my money.

Oh, and just an aside note on the pooling. The very first time I filled my 180 up 6 years ago it got to about 5" in depth and air bubbles started coming from the bottom seam where the brace was. I freaked out, drained it, dried everything down, and smeared silicone over the area where the bubbles were coming from. If I hadn't have done that the bottom bracing would have pooled before the tank was even full, on day one!!! So what he told me absolutely made complete sense.

So, the tank will stay where it is. I will, of course, be keeping my eye on it. There's a good chance next year my 180 will be going anyway. We are looking at getting a wood burner in the living room. Currently my 180(6') tank is in the way of the new proposed fire surround area. However, a 120g tank (4') will allow us to have the wood burner fitted.

I'm hoping i don't have to visit this thread again, because if I do, it will likely be bad news!

 

[fishdance]

What your tank maker says is correct but it doesn't take much extra care or time to make the brace completely watertight. Once dirt or algae gets into the gap it is impossible to remove and makes a bare bottom tank very unsightly. The bottom brace is used to double the thickness of silicon bead along the bottom and long sides so it should be applied at the same time (before silicon skins).

The same applies to cross braces.