Identification help! NOT a hydra...?

[stellers.jack]

Alright, I have been scouring the internet and cannot find ANYTHING that looks like this. Except terrestrial lichen. Growing colonies of white cup-tipped... something. They grow on any surface, including directly on java moss, but seem to like the dead roots of Azolla that have fallen off. I dumped some snail eggs on the biggest colony, which immediately hatched: no effect. Neither seemed interested in the other and baby snails have all gone to greener pastures.

https://photos.app.goo.gl/g9FYcDZDABXaCS889

USB microscope just came in, so you get a closeup. The video is the most interesting: You can see water currents in the top of the frame from the beating scillia on surface of each of the cup-like tips. The needle is 0.36mm dia for scale. The twin brown threads leaving the frame are dead azolla roots. There is a flatworm that was investigating the center, but didn't seemed bothered at all by the tips. Assuming hydra have nematocysts, I don't think this is a hydra.

In case it isn't obvious, buy your aquatic plants from reputable sources...

https://photos.app.goo.gl/g9FYcDZDABXaCS889

 

[Autumnsky]

Did they hatch yet? Do they swim around like that?

 

[stellers.jack]

Aquarium Microfauna

Finally figured it out!
They *definitely* aren't eggs: https://www.msnucleus.org/watersheds/mission/plankton.pdf

So far I have Ciliates – Peritrich (pictured and I can see the effect of cilia under the microscope)
Possibly Dinoflagellates?
A couple Oligochaetes
Possibly a roundworm
Large amounts of Copepods and Water fleas

The weirdest part is the Ciliates go through some sort of life cycle where they turn back into roving organisms that form colonies in the shape of webs before attaching themselves.