I treated on Friday night with Jungle Parasite Clear.
The gouramis seem okay, though they seem a little less active than I remember in previous weeks. The tetras all seem fine, as does one cory.
The cory photographed above has remained very lethargic. I actually got the net out this morning thinking he was dead, only for him to swim off a little before resting again.
I just went to check on him once more and discovered the upper part of his tail fin is missing. It's very clean, no ragged edges. I'm guessing one of the others must have started to feed on him.