This spring I want to attract wild gray tree frogs to my garden. Im planning on putting a livestock drinking container in my garden. BUT, my garden is home to way too many slugs and I need to stop them from destroying my plants before they flower.

I dont want to use salt,it will ruin my soil. Poison no, it might hurt the frogs. Would the frogs be hurt by diatomotis earth? It slices up the slugs and kills them. Would it cut the frogs tender underside or thier feet?
Thanks very much, Robin.