I'm sorry guppy lover if I came across as being rude, that was not my intention at all! But you did say EVERYTHING you ever read about table salt is bad for fish. I agree with SM too that clean water is very important with any type of ailment in fish. But I was just relating my experience with my bettas that I've kept the last 5 years or so and the table salt has worked for me with any type of wounds or torn fins if used correctly. As far as iodide most table salt if you read the ingredients does not contain it. Just was trying to help the OP out because he/ she sounded so desperate!! Is it something I would recommend putting in the tank with every pwc.......,NO. But with my experience with any of my fish table salt works to speed up the healing process in torn fins or wounds, aquarium salt works well for bacterial infections or ich etc Epsom salts works for bloat and constipation. A friend of mine that has a lfs store has even used Epsom salt in his tanks to treat pop eye and said it worked great! He has had a LFS store for 20 years and been very successful and gives me a lot of great advice! But the key once again is based on my experience and his and using it in the proper amount, you definitely don't want to over do any of these types of salt or yes you could have negative results.