In this case, there's really only one solution I can think of... hand picking. Sorry, its not the best. Pond snails are extremely prolific breeders when conditions (aka, excess food is available) are right. Keep feeding to a minimum. Try to feed specifically where your trumpet and ramshorn snails are... but expect that a good amount of that food will end up in the stomach of the pond snails too.
Lettuce leaves hung on the side at night are good snail traps. The easiest way there would be to pick off the snails you want to keep and throw the leaf into the garden after that. In this case, you'd want to get to the 'trap' before light hits the tank. The snails often leave before morning.