Prime adds a Hydrogen atom to the
NH3 (ammonia) to make it NH4 (ammonium). I love
this, if you can make sense of it. The problem is that your
pH can drop, fast, if you've got a lot of ammonia and try to solve the problem with Prime. Been there done that. Good thing I had only hardy Platies.
Also, pH isn't the end-all-be-all of water measurements. Hard water has a higher pH partly because it's got minerals to deal with the free hydrogen atoms.
Acid = low pH = more free Hydrogen
Base/Alkaline = high pH = less free Hydrogen
A bubbler will also help quell those pesky free hydrogen atoms. I mean, your pumping oxygen and carbon dioxide (and nitrogen) through the water (OK, you're agitating the surface, whatever), so those hyper-friendly little hydrogens just glom right on.
Lots of people use baking soda to bring pH up, but it really is unstable (bicarbonate means carbon, and carbon, unless it's pressed into a diamond, is pretty unstable).
It just bugs me that it's so freakin' confusing to figure this out online.
Also, people are trying to solve problems with Prime that it wasn't meant for. It's meant to treat new water to add to a tank, it wasn't meant to let people cycle an overstocked tank just so someone can have lots of fish right when they get their new setup. Fish-keeping is a great lesson in patience and diligence. I'm not sure I'm up for it, but I sure learned a tankload of chemistry just keeping the one I have alive.
I meant to say, too, that the
API test and most strips will measure both Ammonia and Ammonium. The Seachem plastic meter, that will last two weeks at the most, only measures Ammonia. If you use both, you can see directly what the Prime is doing.