These 2 photos are of the same individual a few minutes apart. It had several food vacuoles containing cyanobacteria, diatoms, and other food. It had a few rows of oral cilia around its anterior end, and rows of shorter somatic cilia. It was free swimming but did tend to wedge itself between clumps of soil aggregate and stay mostly still while it filtered with its cilia, contracting back somewhat quickly from time to time. I didn't notice any obvious type of attachment structure at the posterior end. Is this a member of Heterotricha? Here's a short GIF (sorry for the low quality). This one was one of the largest ciliates I've seen, though I normally look for ciliates in soil and compost samples where they tend to be a bit smaller.
The next specimen:
This one was smaller than the first, probably about a tenth of the volume. Its body shape stayed more consistent, and it had a distinct oral structure at the narrow anterior end. My guess is it's from the class Litostomatea but I'm not at all sure. Here's a short GIF of it in action