How long is silicone good for?

[Mythicalelf]

Like how many years before a tank has to be resealed if ever?

I'm wanting a large tank and it is a lot cheaper to buy used if/when I find what I'm looking for.

I'm just wondering what I need to look for, is it hard to reseal one.

[ca1ore]

I had a 180 for almost 20 years before selling it and I believe it remains functional at 25 years old. Key in any used purchase is abuse levels mores than just age.

[Mythicalelf]

So pretty much as long as no peeling it should be good.

What if it has been sitting dry?
Would that effect it?

[billdogg]

My 150DT is about 25 years old. After about 12 years of constant use including 2 moves, it sat, on edge, in my garage for 7 years while I finished the basement. It's been beack up for 8 or so years now without problem. The 120 that serves as it's refugium is at least 35 years old. If the tank has been reasonable well taken care of, it will be fine.

[ca1ore]

So pretty much as long as no peeling it should be good.

What if it has been sitting dry?
Would that effect it?

I guess it depends on the 'peeling'. A bit of flaking is no biggie; happens in most tanks if you get a bit too close with a razor scraper. As long as the silicone is good between the panes, then the tank is sealed. If a tank leaks such that a new bead of silicone is required around the inside edges (playing no structural role) than I'd not use it. Bigger problem I'd think would be scratched glass, so never buy a used tank sight unseen.

AFAIK, silicone does not dry out, so standing empty isn't a big deal.

[Mythicalelf]

Ok thanks for input billdogg and ca1ore.

I won't be buying sight unseen for sure just was checking on buying used large tank.

I bought a biocube a few months back used and it was in nice shape with only a couple tiny scratches on glass. Sad thing is they still bother me a little, my wife says I'm crazy.