You are on the right track. Loaches are among the best fish to use for snail control. They will take care of the snails and also will do great in the same water conditions as the fish you already have.

Flying foxes

I like Clown loaches, they are very lively among groups and will make you laugh as they try to sleep on top of each other, plus like paparoseman said they will aid in the snail problem.

Unless you have a very large (100+ gallons) tank don't go with clown loaches. Instead find some Kuhli Loaches, they only grow to about 4 inches and not only do they eat snails, they will sift detritus on the gravel bed.

It will take about 6 years for a clown loach to get upto 4 inches.

Clown loaches do better in groups. Clown loaches of any size will eat snails.