Snails poop more than I expected. In fact, they funked up my tanks more than they cleaned them! I mean there was an insane amount of poop when I started to vacuum the gravel tonight, which I do every week. This was the first time since adding the snails last Sunday. There was so much of it that I ended up having to do full water changes for both tanks, which hopefully won't cause them to have to cycle all over again, but probably will.
The stinky pewpy snails are now in their own little tank in the bathroom, til I figure out something better for them. PEWPY SNAILS.