I have Zebra loaches (Botia sriata) in with my discus and they are excellent tankmates! IMO they are better than corys - they will school, stay small, are comical to watch, peaceful, will eat anything, do well at discus temps, and control snails to boot.
You need to do your research as some loaches can be rather aggressive or get fairly large. My guess is you are talking about a Yoyo loach, which I have in a tank with angelfish and they do well in there. Not sure about how they handle the higher temps needed for discus, but otherwise should be fine.