I have both of these type of snails too.
In my larger tank I must have a fish that eats snails, I have actually been wondering who it would be, because the numbers in that tank are small and its a four foot tank. When I gravel syphon this tank there are heaps of empty shells that get sucked up.
In my 60 litre tank they are in bigger numbers and I just remove as many as I can or suck them up when cleaning and tip them down the plughole.
Any ideas out of my fishies in the big tank as to who the snail eater would be I have angelfish, gouramis, a siamese fighter, congo tetras, serpae tetras, a golden algae eater, a golden ram, and a bristlenose plec.
I am guessing one of the first three but not sure. Any ideas?