[zevv]

One of the delights I discovered over the last few years is constructing and maintaining sweet water "jarrariums"; I take whatever glassware I fancy - pots, jars, glasses - collect some soil and plants from an interesting pond I find somewhere, put it in and just let it do it's thing - don't interfere, just wait.

It's amazing how much life lifts in with just that bit of soil; I have a few jars from three years ago (that I leave mostly closed) which have shown multiple generations of woodlice, water snails, little mussels, spiders, water fleas, beetles, worms. Sometimes, the whole pot turns opaque green for a few days, and then a few days later it clears up and I find some new life in there I have never seen before.

Highly enjoyable to have on your desk or in the window sill!

[zevv]

And of course there's a reddit for that: https://www.reddit.com/r/Jarrariums/

[technothrasher]

I sort of fell into making one of these as a kid. I had a left a jar of water on the window sill in my bedroom absentmindedly. I noticed later that a wasp had fallen into it and drowned. Then I noticed it was starting to get fuzzy. Then a couple flies also fell into it. I thought it was interesting, so I threw a bit of algae from a fish tank in and sealed the jar closed. It grew into a big green blob and stayed green and "healthy" for at least twenty years, certainly well after I'd left home. But one day I went back to my parent's house and it was gone.

[stcredzero]

I suspect hermetically sealed enclosed mini ecosystems are going to take on tremendous economic and technological importance as we move out into the solar system.

I've started to wonder why there aren't more closed loop experiments out there. These would be very cheap to make! (By space research standards.) A closed water loop habitat could be built in the middle of isolated land, like West Texas. Go from there to incrementally incorporating more of an ecosystem. Try and recycle the air last, of course, as that is potentially life threatening.