Carrisa,
I dont know about ammonia readings,BUT,do not add any copperbased meds when using prime!You will have a QT tank full of very dead fish in nothing flat
The best way to deal with ammonia levels in QT is a functioing biolfilter,or lacking that,water changes.
The best case scenerio is to establish a QT tank before the DT is setup, and ready to receive fish/inverts.