Howdy,
I am struggling with the appearance of vermatid snails. They started out in small groups but now it's like every inch of my rock is covered. On occasion I will go in with a butter knife and hammer them, however, they always come back. I have ~10 tiny bumble bee snails which seem to do nothing.
What else can I do? See some photos below.

I am struggling with the appearance of vermatid snails. They started out in small groups but now it's like every inch of my rock is covered. On occasion I will go in with a butter knife and hammer them, however, they always come back. I have ~10 tiny bumble bee snails which seem to do nothing.
What else can I do? See some photos below.






