Sorry for your loss...
Originally Posted by lvandert
+1 Lebron. 10 days is the max you can do a salt treatment before it starts to affect organs
Actually, Epsom salt is very gentle and safe for bettas, and they can live in it indefinitely.. it's AQ salt, where 10 days is recommended amount of time, can be safely in there for 14 days... but it takes longer then that before it actually damages the organs, you just don't want them in there longer then 14 because it is hard on the fish in general, etc.