Aquariums

[Artois]

Live rock? Are you talking undergravel filtration?

I kept community freshwater tanks for about 25 years, been through many systems. I swear by the undergravel filters and the 10% weekly changes.

The vinegar washing of accessories is by far the best and cheapest way to keep things clean.

Nope. For saltwater, under gravel/crushed coral filtration has been out of style for over a decade. Even if you vacuum it weekly you'll experience deitrus and nitrate buildup. Corals and a good number of saltwater fish really struggle to thrive under those conditions.

I'm referring to actual broken rocks gathered from actual reefs in foreign countries. Like this: http://premiumaquatics.com/aquatic-supply/Liverock.html

It's really porous and filled with beneficial bacteria that will actually filter your water through the nitrogen cycle. Additionally it often brings a host of hitchhikers to your aquarium. Small Copepods (essentially aquatic bugs that fish love), star fish, worms, sponges , corals, crabs, and even more exotic surprises... Not always good though. It's also usually covered in colorful coralline algae, the hard colorful (typically blue) crust that covers most things in a tropical reef.