Bubbles In Resealed Tank

I just bought a used tank and resealed it. First time ever resealing a tank and was pretty proud of my work. Unfortunately, I was ready to fill it with water (had water tested previously with no leaks) and noticed a ton of tiny bubbles all along the bottom seal on all 4 sides. The sealant on the sides of
the tank are perfect. What did I do wrong? Do I have to reseal the whole tank or is this a normal occurrence? The bubbles weren't there when I water tested it but it was sitting for a couple of weeks with about two inches of water in it until I dried it out today and saw all those little bubbles.

 

Welcome, are you sure the glass was completely dry? It looks like moisture under the silicone.

 

Yes, I let it dry out for several days. I'll try one more time to reseal it

 

You are removing the old silicone first right?

 

Yes, unfortunately. I'm assuming I have to take off all the silicone. I was hoping to just remove the bottom silicone that has the bubbles but I believe new silicone won't adhere to old silicone even if it's only a few months old. So all the silicone has to be redone.

So I started taking off the silicone and realized the bubbles aren't actually in the silicone I placed down but in between the base and the glass. The base is glued on and can't be removed.
I'm assuming the tank is shot?

 

I'd give it another shot, how big is the tank?

 

75 gallons

 

wicca1971 I know your pain, I had to reseal a 90g twice yesterday. I didn't work quick enough the first time and it turned into a bubbled crackled disaster. Its easier to clean off now than what you removed the first time. Yes, you do have to clean it all off, silicone won't bond to silicone so where the two meet you'll have a leak if you don't redo the whole thing

 

Grrrr!! It really sucks! Sometimes I ask myself if its worth it? It actually seems harder to get the silicone off this time around. The first time the silicone was literally crumbling off. My fingertips are killing me from scrapping with the razor blade. Ouch! I just hope the frame isn't compromised because water got under it.

 

It will definitely be worth it! I was rather unpleasant the entire time I was stripping the silicone of (for the second time) but once the tank was resealed I felt even more accomplished. I'm giving mine 48 hours to cure so I get to test it tomorrow night! I'm sure you'll feel quite similar once you finish! Good luck!
By the way, don't worry about the frame, its helping to hold it together, but ultimately is just a support. Since this has nothing to do with the seal (in any case that I can think of) you should be good to dry it out and could add additional sealant in there if it makes you feel better. Keep in mind, all this relies on the fact that the moisture came from humidity or setting the tank in water rather than it leaking, but I doubt that its leaking on all 4 sides equally.
Cheers!

 

Thanks for the positive vibes! I'd like to see a pic of your finished project.

 

This is after the second reseal. I'm MUCH happier with it and glad it's over! The project as a whole will take me several months due to costs, but will be beautiful planted tank in the end. The next step is to finish stripping the paint off of the stand and repaint it. The previous owners let it fall into disrepair.

 

Nice!!! This is mine mid silicone scraping. The stand is going to take some work. I think the previous owners had a cat and used it as a scratching post. Hey, question for you? Any tips to get hard water stain off the glass? Previous owners used the tank for turtles and only filled the tank half way. There is a water line half way up the tank that I just can't get rid of. I've tried every trick but it just won't go away.

 

So I started taking off the silicone and realized the bubbles aren't actually in the silicone I placed down but in between the base and the glass. The base is glued on and can't be removed.
I'm assuming the tank is shot?

Sounds and looks like is condensation between the plastic rI'm and the glass, does not affect the structural integrity of the tank.

 

Thanks ganjero. I'm giving it a second go around with the silicone since I thought that was the original issue. Definitely harder taking off the second time.

 

Not sure what to do about the hard water line. I'm assuming that you've already used vinegar? I didn't have to struggle with too much of that given that mine was previously salt water. The tank looks good as does the stand. Do you have any plans to paint/stain it?

 

I tried staining the side that had the cat scratches on it and it looks ok. Not great, just ok.
I think now that I have more time on my hands since I have to reseal the tank I might stain the whole stand. I guess I have to sand the whole thing down first? This is all new to me.

 

yeah, sand it like crazy for the best finish possible. From the looks of it they hadn't done anything to the wood themselves, so that will make it easier. Its going to be time consuming and require a bit of elbow grease, but should look stunning in the end. I'd suggest taking off the hinges to give you better access to both the doors and the stand itself while sanding and painting.
I really recommend testing your stain in a corner on the back to make sure you like the way it looks before applying it to the whole thing. Just my opinion.
If you like them, keep them, if not you can spend a few dollars at the hardware store and buy some brand new ones. Keep in mind the trim around your glass. I personally will probably never mess with mine, I'm too nervous to do so, but you'll want to make sure that whatever you do to your stand matches the trim.

Just tested mine and looks like the tank itself is sealed up nice and tight, though I'll need to hit a seam along the back of the weir along the bottom to prevent a slow leak from the tank into the overflow region (mine is getting hooked up to a 30 gallon sump). Yay progress!

 

I'm starting to freak out now. I've been scraping away and noticed silicone that I just for the life of me couldn't scrape off. Come to realize it's on the outside of the tank. On closer inspection parts of the outside of the glass sides have silicone on them. When I look even closer I noticed the edges of the glass aren't flush where they come together. I'm wondering if this tank was reassembled at some point. I can't imagine it coming off the factory like that.

Keep me posted on your tank. I think I have to trash mine. After posting about the non flush sides I've got a bunch of people telling me the tank isn't stable and will probably explode after enough water pressure is put on it. Why didn't I notice it before???? All that work and I really can't afford a $500 tank but that's what I need.

 

That's a real drag. So sorry to hear that its not salvageable. Yeah, I too am realizing how expensive this hobby can be. This 90 gallon probably won't be up and running until May or so because it's going to cost me about another 750 or so with the rest of the hardscape, plants, fish, and CO2 system, but when I do something, I go hard! Wahoo! I truly wish you the best of luck, at least with a new tank you'll feel more secure about those seals. Keep me updated.

 

Keep me posted on your tank. I think I have to trash mine. After posting about the non flush sides I've got a bunch of people telling me the tank isn't stable and will probably explode after enough water pressure is put on it. Why didn't I notice it before???? All that work and I really can't afford a $500 tank but that's what I need.

Who is telling you this? The sides no being flush is not a big deal, my marineland 300g DD was not flush, and the 120 gallon all glass I have now have sides that are not flush by about 1/16". This is very common for mass produced tanks. What I will advise you is to be careful when messing with the silicone, you do not want to compromise the silicone in between the panels, that is what really holds the tank together and provides structural integrity. I don't even know what are you trying to scrap silicone from outside the tank, even inside all you need to do is remove a little bid only then put a bead of fresh silicone, deep your finger in soapy water and run it along the fresh silicone to give it a nice finish. All you are trying to do (and all you can do without taking the tank apart and rebuilding it) is improve the aesthetics of the tank, and provide some protection to the real seams (Silicone between the panels). "Resealing" a tank doesn't do more than that....if a tank is leaking I would not trust fixing it just with a "reseal" job, leaking means the seam has been compromise and needs to be redone from zero which is taking the tank apart and rebuilding it.

If you don't trust the tank, you could also see if there is someone with experience on building aquarium around you area, and have them give you a quote for rebuilding yours. You can save money by taking apart yourself and bringing the glass panels to them. Sometimes this ends up being more expensive than buying a new one, but it is worth getting a quote. Also depends on the current status of the glass (scratches etc), and comparing the glass thickness of this tank vs a new one. Old aquarium were overbuilt with thick glass, which I would trust more than the thinner glass a few companies use now to save money pushing the limits.