Yes from around 16 earlier in the week I can count only 8 daphnia now.
I've cut the air down to a stream of single bubbles in case that is part of it, and started a new bucket of green water to feed them.
I still want to know what daphnia feeding look like.
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It could just be that they have reached the end of their lives as more reading says they live from 40-56 days and I've had them for a few weeks. Which means they just aren't reproducing or not as quickly as I envisage. I watched one die earlier, it sunk to the bottom and jerked around erratically like in a death throe (very dramatic it was) and sunk. Then every little while it would jigger about a bit and sink again until I gave up watching it. .
I still have my biggest green ostracod and a handful of small beige ones. Copepods/Cyclops are doing very well and there are also some white swimming worm or leech like creatures that are less than a mm wide and about 3 long. Tried to see if any thing was interacting with the mystery fungus creatures, as if eggs etc, but nope.
And the (tubifex?) worms are also quite active. Some waving in the gravel, another crawling about in the leaves and another crawling about on top of the wood.