They have to ingest it via flake food.I tried it, it did not work.
I can post my YouTube video as proof.
Give me a few minutes.
I looked, I don't have a video, my apologies.
I have a video using ivermectin. For sure that don't work. LOL
But, I did use fenben on bcp. Vermetid survived.
I also want to see this video. I'll watch it when I get some time.
Until I see with my own eyes dying snails, I'm not a believer.