Water level had dropped by cca 2cm so I topped it off with alkaline bottled water. The plants are well and alive, have seen nothing changing colour or otherwise rotting. Little bubbles of gas have formed in between the weeds, like marbles. Am wondering whether it’s oxygen.
One way to know would be to capture a reasonable volume and shine white light through it to see emission and absorption lines – but that would be significantly more involved than it sounds.
I can see no dead bodies of organisms on the surface, on the bottom or in between the weeds. The mosquitos I killed have disappeared.
I dropped a crumb of bread in the water in an attempt to lure the snails so I could count them. It somewhat worked – there were snails feasting on it for a couple of days but no way to have them all there at the same time. The bread was broken down into a hazy mist which smaller organisms are probably eating now.
There are 3-4 large snails measuring now about 4mm. Many smaller ones ranging from <1mm to about 2mm. They are so small and light that they can actually slide about while upside down, using the surface tension on the water surface.
The water plant has now emerged and there are brown hairs growing out if the stem – i suspect it’s some form of root. They are only visible on the part of the plant which is not submerged. Maybe I should put a stick in the jar with part of it out of the water so things can crawl up on it.
Very happy to have seen a couple of water fleas, quite large and active. Cyclops are dashing around as usual (still no egg-bearing females).