I know, and I wasn't suggesting you were going to. It's just that brackish fish will not do well in full marine or full fresh (a few exceptions). I read a thread about someone wanting to do this with guppies a while back, but don't remember where it was. One of the commenters had some great information regarding why fish need certain salinities. I'll look for it.
Anyway, this is all just my opinion, of course, but freshwater fish should stay in freshwater, salties in salt, brackish in brackish.
But I'm also the guy who is strongly against any pet of any sort ever eating people food (irritated my ex gf with that one. LOL)
Someone stop me! Please! But... not just yet...
55 Gal Tropical FW
55 Gal Mixed Reef