The options easiest to install in a condo often protect you from too little. The options hardest to install often remove too much from your water, and in most condos and apartments, aren't really an option at all.
Ordinary Carbon Filters Let Hundreds Of Dangers Pass Through
Carbon-based filtration systems are available in several forms that work in a condo or apartment. Faucet-mounted filters, for example, don’t require any drilling. Some under-sink carbon filters can connect without a second dedicated spout.
However, the technology remains an issue regardless of which form you choose…
Basic carbon filtration is built to target chlorine to improve taste, but better taste doesn't mean better water. After all, that same carbon technology wasn't designed to catch lead, PFAS, pharmaceuticals, microplastics, and hundreds of other dangers found in public water supplies—including the ones most likely to show up in the shared pipes of a multi-unit building.
Of the 324 contaminants detected in U.S. tap water, basic carbon filters typically target as few as 5. That’s why relying on a carbon filter to protect you and your loved ones from the dangers of tap water is like trying to catch the ocean with a coffee cup.
Reverse Osmosis Removes Everything, Including Healthy Minerals
Reverse Osmosis (RO) filtration systems sit at the other end of the spectrum. And for most renters and condo owners, the installation requirements end the conversation before it starts. RO systems often require a dedicated faucet, a drain line connection, a storage tank, and potentially a plumber.
Countertop RO systems, on the other hand, were designed to get around all of that. There’s no dedicated faucet, no drain line, and no drilling required. But these systems occupy permanent counter space that was already scarce and often require filling a tank manually before the water is filtered, which puts you right back where you started.
Even if the form weren't an issue, the technology would be…
RO forces water through a membrane that removes nearly everything, including healthy minerals like calcium, magnesium, and potassium. In other words, the technology doesn't distinguish between what should stay and what should go. Without those minerals, many describe RO-filtered water as tasteless or dead. Meanwhile, many RO systems discard 3-4 gallons of water for every 1 gallon they filter.
Put differently, more filtration isn't always better filtration.
What About Everything Else?
Beyond carbon and RO, there are other filtration technologies and proprietary combinations on the market. Ultrafiltration systems, for example, use a fine membrane that blocks bacteria and cysts while letting minerals through. But these systems typically don’t filter dissolved contaminants like fluoride, nitrates, or arsenic.
Other systems layer multiple technologies together in hopes of covering more ground. Some do. But any system built around a reverse osmosis membrane brings the same installation requirements and the same mineral problem, regardless of what surrounds it.