Not sure about that, but I have been intermittently using the same 40g breeder for freshwater and saltwater since 2010 with no issues to date (currently in use). About 20 years ago I got a free big hexagonal tank from my dad's friend that was about 20 years old at the time and it held water like a champ for years before I had to give it away during a move.
So, I guess what I'm trying to say is that a well-sealed tank can last a really long time.
Is anything particular giving you a reason to not trust the silicone on the 125g?