Get both your discus into the 10g QT asap
. Raise the temp to 88F gradually. Add 2 tspn of aquarium salt. Do not add salt to the tank with the clown loaches.
Pick up a product called Flukes Control. It is pure patassium permanganate. If it is flukes you will have to treat for 3 weeks. Many times though, bacterial gill infections look like flukes.
Describe the symptoms please. Again, I highly suggest you raise these fish in a seperate tank. Their needs are different from adult discus and at 2 - 3 inches they are very fragile!!!!!!!