Here’s a fun one: RO systems can actually remove dissolved gases like radon—sort of. Radon is a gas, and gases slip through the membrane like a fart in a crowded elevator. So you still need a carbon filter after the RO to catch those stinky ghosts.
Also, did you know that the first commercial RO membranes were used to make seawater drinkable? Yes, sailors used to drink salty death water until the 1950s when some genius at UCLA said, “Let’s squeeze the ocean until it cries pure water.” Now you can do that on your countertop. Humanity is incredible and also ridiculous.
And here’s the kicker: RO water is so pure that it can actually leach minerals from your pipes if it sits too long. That’s why some systems add a “remineralization” stage—so your water has enough calcium to not be a thirsty predator. Otherwise, you’re drinking water that’s basically a hungry ghost.
