You Should Never Leave Water In Your Nespresso Canister. Here's Why

The truth is, we all feel lazy sometimes. Blurry-eyed with sunrise cracking through the blinds, it's tempting to leave that Nespresso canister half-empty, but you need to fight that urge. Old water can make you unwell and ruin the taste of your precious cup of Joe.

The biggest factor is the deterioration of its protective qualities. Tap water is protected by chlorine, a chemical artificially added to kill bacteria. Yet, chlorine can evaporate in as little as 24 hours. Because of this, a Nespresso canister quickly becomes growth-friendly for new colonies of bacteria, and creates a favorable environment for dormant ones, such as Legionella, to reactivate — especially at temperatures over 68 degrees Fahrenheit. The longer that water sits, the higher that risk becomes. In some cases, contaminated water tanks could cause nausea and stomach cramping.

There are plenty of false facts you shouldn't believe about your Nespresso; don't be fooled by the myth that leaving water in the canister is okay. It's worth noting the quality deterioration, too. The reason water tastes differently after sitting out for a long time is the absorption of CO₂. Leaving Nespresso tanks half-full is a one-way ticket to an acidity spike, and the last thing consumers want when balancing the delicate pH of coffee is off-tasting water.

Side-eyeing that Nespresso machine? Good. It's essential to take water safety seriously; nobody wants to accidentally sabotage their morning coffee ... or stomach. 

Daily changes seem to be the sweet spot. Will a half-empty tank that's been sitting for over 24 hours do harm? It's a similar question to whether it's safe to drink that glass of water you left out overnight; technically, no, it won't hurt you, but it's not worth the quality deterioration or risk. There are quibbles over hard vs soft water, and which to use to brew coffee; swapping acidic-tasting remnants in a tank is the least of your concerns. It's better to have peace of mind. Refilling on a daily basis eradicates concerns over evaporated chlorine, while reducing the chance of overly bitter coffee.

From a health perspective, the window of concern could be anywhere from a few days to a fortnight. There are always a few outliers, though. "Tbh I only fill it when it's running low," laughed one Reddit user, while another chimed in, "Me too... seems to be unpopular lol." Unless you're emptying a canister per day, steer clear of joining that group.