the bacteria in your tank should be able to process the ammonium in less than the 24-36 hrs prime locks it.
however, at issue is how much bacteria is present in the tank.
a heavily planted tank may not have as much bacteria since the plants would compete with the bacteria processing the ammonia leaving less for bacteria.
I am not sure how much of an impact this would have or whether or not the plants can 'out compete' the bacteria in this case.
the bacteria should be able to reproduce in hours.
an alternative is getting a filter.
filter guys has chloramine filter kits.
the bond created between prime and ammo to make ammonium only lasts 24-36 hours. that's all i can think you might be asking about. if i am wrong please post a link that better explains it.