Gumby go get a 10 gallon rubber maid container, a heater, and a powerhead. That's a good enough QT tank. You want to get them out of the display. What are your tank parameter's like? how long have you had the fish? when did you first see signs of the disease? Do the red splotches look velvety at all.
Do the symptoms look like any of these?
Marine Velvet Common Marine Fish Diseases
I'm no vet, but maybe these can help you determine what's going on, and how to cure it. Keep us updated.
EK