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chrisv
07/09/2017, 11:38 AM
Hello DIY tank builders!

I have a tank that I built a few years back-- its 24" long, 16" front to back and 14" deep. The tank is constructed out of 3/8" glass and is rimless.

I was moving the empty tank and I had an item in the tank and it slid across the bottom of the tank and hit the side and cause a small glass flake (shell/conchoidal fracture) to chip off of the bottom of the side panel. The flake is right in the middle of the panel. There seems to have been a little damage to the silicone around the area of the flake.

Since the tank is relatively over built with respect to seam thickness, my plan is to reseal the specific panel that is damaged. Because in the original build I attached the sides first and then the front/back, I believe I will need to remove the front panel and the side panel in order to reseal the side panel.

My question: Is it okay to only reseal the two panels? Or will in the process of removing these two, will I compromise the rest of the seals. I would rather do this right and not have a flood in my living room.

Thanks in advance.

der_wille_zur_macht
07/09/2017, 12:16 PM
Have you ever disassembled a tank? It's not a delicate operation. I'd imagine it's totally possible to remove only a single panel, but it's going to be hard for us to give meaningful advice because it's going to depend on your skills, really. On a tank that size, personally, I'd probably give it a try - then once I had my desired panel out, I'd carefully inspect the other seams and if there was any doubt I'd pull them apart as well.

chrisv
07/09/2017, 12:26 PM
Have you ever disassembled a tank? It's not a delicate operation. I'd imagine it's totally possible to remove only a single panel, but it's going to be hard for us to give meaningful advice because it's going to depend on your skills, really. On a tank that size, personally, I'd probably give it a try - then once I had my desired panel out, I'd carefully inspect the other seams and if there was any doubt I'd pull them apart as well.


I've actually never taken one apart...only built them. When building I have always been paranoid to assemble and clamp all the panels together ASAP, to keep the silicone from setting up on me.

The reason I'd take the front AND side off in this repair is that the side panel is sandwiched between the front and back panels, therefore, getting it back in with an appropriate silicone structural seam would be difficult.

JTL
07/09/2017, 12:33 PM
I have done this and I can tell you it is a lot of work. I' m not sure why you are even contemplating it. If a little silicone is missing just clean the area real good with actetone add some new.

If you are hell bent on removing the panel here is a trick or two. You can use very thin piano wire on even some fishing line to "saw" your way down the seam. I actually found that the blade from a disposable razor worked very well. They are super thin, but obviously you need to get it out the razor.

Then you must clean the glass of ALL silicone, bring it back to virgin condition. This takes a fair amount of time, but new silicone does not have nearly the adhesion strength as new if you apply to old silicone. I don't know what was used originally but I use MTV from Momentive and that stuff is incredibly strong. I just finished 50g sump and made a mess on the baffle seams and i have no intention of doing them over. I would rather build 10 tanks than mess with baffles and 1" spacing.

chrisv
07/09/2017, 12:52 PM
I have done this and I can tell you it is a lot of work. I' m not sure why you are even contemplating it.

I am thinking of doing it because when I look at the structural seam from underneath, there appears to be a hairline air bubble that has formed in the silicone seam that radiates from the center of the flake but go mostly parallel to the pane of the side panel.

If resealing only two panels wont compromise the rest of the tank, I think I will just sleep easier knowing that those hairline bubbles in the silicone are not expanding to the edge, leading me toward a catastrophic seam failure.

If it were near the top of the tank I would be less worried.

This said, the glass is 3/8" glass, which means that there is a relatively wide seam given that it's only a 14" deep tank.

I've included a picture.

Lsufan
07/09/2017, 01:38 PM
If it was me & I was pulling two panels off anyways I would just rebuild the tank. U obviously have experience if u built the tank in the first place.

Judging by the pic the seam doesn't look to bad & is probably fine if it has been like that. There is still plenty of silicone in that seam. Now if the damage is what caused it then I would be worried about it getting worse.

Btw, I'm no tank builder but I have built a couple about your size so I do have experience. So this is only my opinion & not one of a tank builder.

chrisv
07/09/2017, 02:15 PM
Judging by the pic the seam doesn't look to bad & is probably fine if it has been like that. There is still plenty of silicone in that seam. Now if the damage is what caused it then I would be worried about it getting worse.
.

I believe that the silicone damage was caused by the Impact that caused the fracture :(

All of the other seams are in great shape so I'm hesitant to screw with them. Any idea if only resealing the required seams will cause a problem down the line?

JTL
07/09/2017, 02:39 PM
Looking at the pic I personally would not worry a bit and I am very anal about that stuff. You may not have noticed that very small void was in the seam all along. It is in the middle and so small to be inconsequential imo, but if you can't sleep nights go for it. It is going to be a lot of work. Once you start taking it apart you will quickly see how strong these seams are.

The other thing you could do is put a eurobrace around the bottom.

der_wille_zur_macht
07/09/2017, 07:13 PM
I believe that the silicone damage was caused by the Impact that caused the fracture :(

All of the other seams are in great shape so I'm hesitant to screw with them. Any idea if only resealing the required seams will cause a problem down the line?

As long as you don't disturb them it shouldn't be a problem. Seeing the photo, personally, I'd proceed with the work.

chrisv
07/09/2017, 08:05 PM
On further inspection I found another fracture/bubble. This one is on the outside on a vertical seam. One of the ones that would be redone if I resealed the front and side. Here is a pic. What do you think? Two strikes?

chrisv
07/09/2017, 08:07 PM
Here's the picture.

JTL
07/10/2017, 06:26 AM
The latest pic is worse, but probably not catastrophic. Are you sure these weren't there from day one? Remember when you see an air bubble or void in the seam that is a very small issue in terms of strength. Most silicone adhesives have off the charts holding power per square inch. However it could result in a leak if it compromised the seam entirely. The bigger issue in my mind is did this happen after you used the tank and is that indicative of more separation to come?