All loaches are active fish requiring high Oxygen levels. As water increases in temperature, it's ability to retain dissolved Oxygen decreases, (it has a negative coefficient of solubility), thus the warm water of a Discus tank is never going to suit loaches.
I remember at my fish club's open shows, if they were held on a warm day, we always had to use battery powered air pumps to stop the loaches turning over during judging/display, and early de-benching was usually allowed in that class. They were only in the tanks for a few hours.