Can I reseal only part of an aquarium?

[nataniah]

Honestly, the tank in post #1 looks to my eye to be completely safe for use. The silicone between the glass panes is what holds the tank together and provides structural strength. It's usually a continuous seal that maintains the waterproof integrity of the tank as well; the extra little concave bead that, in this pic, shows a bit of a ragged edge, is there just as an added insurance against leaks. If this tank doesn't leak now, I doubt it will at any point in the foreseeable future if properly set up on a flat, level stand.

N nataniah , sorry to say but the spot where your old silicone meets the new is a problem. However, it looks as though you scraped off the old silicone from the upper half of the corner and then re-sealed? Definitely the wrong way to do it, but it's done now so why not try it out? Any leaks will likely be visible within a day or two.

Whenever you apply silicone, you really have one good chance to make it smooth and neat, right when it is first applied. If you keep poking and squeezing and fiddling on the bead, trying to get it right...which is what it looks like you did...it just gets uglier and uglier. Same if you wait more than a minute or so to "tool" or work the surface. Lay it down, wet your finger and swipe across it once. Practice makes perfect.

If I notice that there are leaks should I just reseal the whole thing?

 

[jjohnwm]

If I notice that there are leaks should I just reseal the whole thing?

At that point, a complete re-seal would be pretty much the only logical step. Be careful to remove only the exposed bead inside the tank, without cutting into the structural silicone inside of each joint.

It's a PITA; worth doing once so that you learn to avoid tanks that need that kind of work in the future... For the cost of a 30-gallon tank, I'd probably just buy a new one.

 

[nataniah]

At that point, a complete re-seal would be pretty much the only logical step. Be careful to remove only the exposed bead inside the tank, without cutting into the structural silicone inside of each joint.

It's a PITA; worth doing once so that you learn to avoid tanks that need that kind of work in the future... For the cost of a 30-gallon tank, I'd probably just buy a new one.

Thank you so much! Are there any youtube channels or videos you’d recommend? I’d like to watch a couple before I try a complete reseal!

 

[Cich Mind]

I'm prepping an old 55 gallon and I noticed the silicone is slightly damaged towards the top. Tank still holds water as it currently is. It's it possible to only re silicone this small 3 inch section or do I need to do the whole aquarium? Do you think I'm safe leaving things as they are since it still holds water?

What's up C Carefree_Dude and N nataniah . If you decide to reseal your tank there are a couple of very useful and cheap tools you can use. You can find them at Home Depot, ect. These tools are something you would use for caulking a bathroom or kitchen. One is a small scraper that is at a 90 degree angle that makes removing silicone from corners much easier and quicker. You'll probably still need to use a razor blade for the tougher spots though. The corner area were the silicon goes has to be very clean as others have said. The other tool is a small detailer. After you are done cleaning the corners and starting to apply the silicone you run the detailer ( a small square piece of rubber material with rounded corners ) along the silicone bead as you go and it gives it a clean professional look and less mess.
HTH

 

[Ulu]

When you do this job, the important thing to remember is you do not want to dislodge the silicone captured between the glass.

Glass tanks are so inexpensive now that I don’t think it would be worth anyone’s while to reseal anything smaller than a 30 gallon.

I resealed my 30 tall and it didn’t bother me to do that because I knew the history of the tank having bought it brand new.

I would not spend that kind of labor on a tank with unknown history. I knew how old the existing silicone of mine was, so I knew what I would end up with.

But with the used tank I would not have a clue how old that silicone on the tank was. Lacking the knowledge I would be inclined to cut the entire tank apart, strip every surface, and rebuild panel by panel.

On an inexpensive tank I don’t think I could bother. If I got a really good deal on a really big tank, my opinion might be different. In that case it all comes down to the condition of the glass itself.

EDIT.....Of course I am speaking in hypotheticals here. I’m running eight tanks right now and I’m trying to figure out how to get rid of a couple.