Brandon I think the Reverse Undergravel filter has a lot to do with that. During a power outage, and there have been many, once for 5 days, the UG filter doesn't seem to have any negative effects. I run it very slow so the bacteria throughout it are not used to a lot of oxygen. Just a little.
I could and did also pour water into a funnel that feeds the UG filter every couple of hours to keep it oxygenated. I don't think I had to do that but it didn't hurt.
No one uses a reverse undergravel filter even though mine lasted so long with not even one problem. Many people ask me if I started a new tank if I would install a "better, more modern system".
Like really!!!! What system is better? Sand? I don't think so. Bare Bottom? Not likely. That would be the worst IMO as the bottom of the tank is all surface area and gravel just increases area for bacteria to live and bacteria runs our tanks not us or Supermodels.
I also think, and I know it is very controversial that the act of quarantining and keeping fish in a tank with no fresh live bacteria or pathogens is the reason most tanks crash and the reason there are no old quarantined tanks. I feel that method causes disease, not the other way around. Again, just my opinion.
I think the "secret" is to keep fish like they are kept in the sea, fully immune from everything and it is very easy, much easier than quarantining.
This week I bought two new fish and this year I bought a few more because some jumped out. No problems. I also think most people just don't know or don't want to feed correctly and I cringe when I see what people feed their fish, then they wonder why they are on the disease forum.