The freshwater ammonia reducing stuff does not work in saltwater, since it absorbs one of the ammonium ions and not the other, which differ in their relative concentrations in solution in saltwater vs. freshwater.

Hmm upon reading this, I'm not sure if it makes sense, but it is elementarily right without a discussion on water chemistry in saltwater vs. freshwater. I'll try to get you a link, I read an article about this somewhere.

The ammonia remover I have comes in this 2L milk carton thing. It is for SW. I used it for the first year or so when I first started out. But I replace the mechanical filters with a phosban reactor and have only been running carbon.
Thanks for all the information everyone.