In January, we scooped up some lake water and sediment samples near the mouth of Hoisington Brook in Westport, NY. We looked at it under the microscope and there wasn't much to see. We left it in a clean fish tank for a few weeks and we same many microorganisms including algae, paremeciums, vorticella, and some things that look like egg cases.
This is a video of a paramecium feeding on algae. There are also a couple of voticella at the beginning. The paramecium and some other organisms were found in a water sample from Lake Champlain.
These are some kind of egg cases.
Here is a video of a vorticella: