“About a week ago, I scooped up a jar of murky water from a local pond, sealed it up and put it on my windowsill as an experiment in making a sealed ecosphere,” the YouTuber tells in a video which now has over half a million views.
After one more day passed, the water in the jar cleared up even more and this time, the creator of the ecosphere could make out some small crustaceans. “Later I started to see daphnias too,” he says in the video.
Which turned out to be a hydra—a carnivorous freshwater coelenterate
“There are also some little specks that seem to move in a sort of spiraling-swimming motion,” the voice-over in the experiment video tells us. “[I] think these may be single-cell organisms such as ciliates, possibly paramecium.”
But there are more and more of them with each passing day
One interesting note was that “the hunting methods of the hydra are actually quite wasteful. I caught quite a few shots of it capturing and stinging a prey animal only to later drop it without eating it,” the experimenter says.
Watch the video of the glass jar over the first week