I agree with what you said to a point, I believe that it is based on the dosage of the prime.
Lets say for example that a drop of Prime detoxifies .5 ppm of Ammonia. If you only had .25 ppm of ammonia in the water then you will still have .25 ppm of ammonia that can be treated with the drop of Prime.
Being a chemical bond between Prime and ammonia I think that it is hard, if not impossible, to convert back to ammonia. (from my rudimentary understanding of chemistry classes in high school)
The way I always thought it worked was: it detoxifies the ammonia in the tap water. Then it stays active in the water and keeps detoxifying new ammonia(from the fish) for about two days. Then after that two or so days the only toxic ammonia you will have will be whatever the fish makes after that point (and that's if your tank is not cycled). That's what what all the descriptions of it seem to say. Do you agree?
That is what I understand from what I read. I am by no means a chemist or a spokes person for Prime but if what I read is correct from the website and some basic understanding from the bottle and personal experiences, it shouldn't change back to a toxic form.
There will always be a refute about what is true or not but I trust the makers of the product.
Okay, on that thread I posted the other day about Prime, someone said that the ammonium can start converting back into ammonia. But if it "locks" ammonia into the less toxic form, then it can't turn back, right? Somewhere on the seachem website it says the bond between the Prime and ammonia is not reversible. Wouldn't that mean that any ammonia in the tap water that was detoxified should stay that way?