I have used coffee grinds, potatoes, oranges, beer, whisky, yeast mixed in water, sluggo plus, and cinnamon sprays.
I found that a mix of sluggo and cinnamon spray does work the best for me..... They all work and yes, mold does grows on sluggo, but will not hurt anything and will wash away.... You may have to apply it more frequently at first to get the stragglers . slug/snails don't die right away but they can't eat anymore. The cinnamon spray will kill the eggs in the mix/soil as well as any other pest. Cinnamon also has anti fungal properties. You can use coffee grinds on the ground as a maintains thing. That really is the key..... maintains.