Ah, yes, I see you mentioned it in post #9, and Callistra replied in post #10. That's how the Epsom salt (magnesium sulphate heptahydrate) conversation started.
Not eating for 3-4 days isn't a big deal. Raised scales are a big deal, though....
Edited to add: Did you do the series of water changes that Callistra recommended, to bring down the ammonia?