The above is a great link.
Also, allow me to quote chichlid forum.com (this is only to address inaccessibility to aquarium salt):Salt:
Salt is frequently recommended for treating a myriad of fish diseases, especially those involving external protozoa and fungi.
What kind of salt? We are not talking about “marine salt” or “cichlid salt” (both of which typically contain a blend of mineral salts and trace elements specially formulated for aquarium use to simulate ocean or rift lake water chemistry). You want sodium chloride (NaCl). “Aquarium salt” is the most widely used form because it does not contain the iodine or anti-caking agents that table salt does. I will say, however, that several credible sources assert that the minute amount of additives in table salt are harmless. Robert T. Ricketts, writing for AquaSource online magazine, puts it best with “any water-living vertebrate would be pickled in brine well before toxic concentrations of iodine could be reached.” Still, others offer strong warnings about the dangers of iodine and prussiate of soda (an anti-caking agent) and suggest “canning salt” as a cheaper alternative to aquarium salt. Make your own choice, but since I’ve heard only warnings and no actual accounts of fish death by table salt, I assume it’s most likely the ‘better safe than sorry’ principle at work here. “Sea salt” is another option, and is generally available in nutrition stores because it is considered a more “natural” form of salt. It does not contain iodine, but may have anti-caking agents. I have used it in my aquariums without incident.
The above can be found
again, i am only addressing your one statement. however, BOTH links have TONS of info you may find invaluable.
Best of Luck! :)