Left pitcher of water standing in kitchen for 4 weeks

What kind of germs / amoeba can I expect?

If it was uncovered and it was tap water or purified water, you will get a small bit of whatever airborne bacteria that survived the journey on a piece of dust, along with some molds, and just a larger population of whatever bacteria was already in the pitcher before it was filled. Basically the same stuff you breathe in and get in your mouth every day, likely in larger numbers. Amoeba excluded from this because they are irrelevant even if they were in there, they wouldn’t cause any harm unless this is river water in question. The absolute worse thing that would happen is that you drink it and it upsets your stomach for a few, but I doubt it., Not much else will happen, plus it probably will taste how your kitchen smelled, maybe something you cooked a few weeks ago lol. If it is germ fear, just rinse it out if it smells and wash it with your other dishes, and it’ll be ready to go again.

If it is germ fear, let me put it this way. I have a water dispenser (I usually leave the top off, helps it flow better) that i fill with filtered water every 8 days, the water sits in there for over a week until it is all gone (drinking it) and I just rinse it with tap water and fill it up again. I’m still here, typing about it and have been drinking out of that dispenser for nearly two years, never washed, just rinsed out.

There are few nutrients in clean water, so the only things that will grow in it are those things that can survive on whatever dust floats into it. In a typical household, most dust is tiny bits of skin from the mammals that live in the house. And the bacteria that feeds on that is already ubiquitous on the skin of those mammals. You’re not going to catch anything you don’t already have.

You might also get some photosynthetes in there, if the pitcher is next to a window.

Makes sense, thanks!

Good point. I’ve noticed things like the clear water reservoir of our Keurig-type coffee-maker gets a thin film of green algae after a few weeks if we keep the reservoir full, probably because the Keurig is in a fairly brightly-lit spot. The “aquarium” problem.

:confused:

What, you’ve never seen a pitcher window?

A cute and fun thing to do with kids is to head out to a stagnant slough or creek with a quart jar … half fill the jar with bottom sediment and the rest with the water there … bring home and place jar by a sunny window … all kinds of cool things will grow …

Plant life, e.g., algae.

The reason your water doesn’t go bad is that reasonably clean water from the faucet doesn’t have any nutrients for microorganisms. Sure, bacteria and yeasts and molds are floating around getting into the water, but there’s nothing in there for them to eat.

Even photosynthetic algae will have a hard time because although they can get energy from sunlight they still need nitrogen and such.

Of course as has been pointed out, dust will drift into the water and eventually a little ecosystem will establish itself, except the water will also be evaporating. So whether you get murky water filled with crud or a dry dusty empty pitcher depends on the speeds of how fast the water gets enough dust to provide enough nutrients for noticeable microbial life vs how fast the water evaporates at that particular temperature and humidity.

In my house, mosquitoes will breed unless I change water in the dog’s bowl really often.

4 weeks of dead human flesh