Have these clowns been directly addded to the display or the QT
? What are the numbers of your "perfect" readings?
Without more indicators for possible parasite/disease, you might just need to play wait and see. Bumps unto themselves are not always an indication of an immediate threat. I would however suggest a few large water changes done every second day over the next week. Be sure to use well aged/aerated SW
If the spots disappear and come back, you will be dealing with a parasite, most likely C. irritans
but that will need to be determined at the time. If they disappear and do not come back, it could have very well been a mild bacterial infection or the onset of Lympho.