Pass all your water through a diatom filter before you return any of it to the aquarium, or else you're just reducing the number of mobile Ich swarmers. This takes two aquariums. After three days in one tank, you return the fish to the other, which has been emptied and refilled.Tank 2 could be a large covered bucket with filtration running. Keep the heat as high as the loaches can take it: 86oF would be good. As with all treatments for Ich, you have to keep up the treatment several days after the very last possible visible maturing Ich is to be seen on any fish anywhere.