snail-eating fish?

I`ve been using clown loaches for snail control in my 55g planted tank,
but now they`ve grown too large (4 inches +).  Rather than trade them in
for smaller ones every year can someone recommend another good snail
eater that stays under say 1.5 inches or so.  
Other current inhabitants are:

3 neon tetras
3 harlequin rasboras 
3 siamese algae eaters
4 otocinclus
1 corydoras

Include common names if possible as latin gets only blank stares at 
most pet shops around here.  
Thanks in advance,

Stephen Morrison
near Chicago where it`s up to -2 F today...but it`s a _dry_ heat