So at home I have to different types of salts and wanted to know if one is safe for Betta first I have regular salt we use for food then, I have another salt that's more like crystals and on the ingredients it just says salt no other thing added its like salt used in alcoholic beverages like margaritas I wanted to know if I can add that one to my 5gallon tank for my Betta as i think he might have Velvet im also giving him Jungle Life Guard.
Also im afraid of doing a large water change since my ghost shrimp in there has recently gave birth and might hurt the fry? So how should I clean the tank? I have also turned of light near the tank only turn it on to feed him.
Also I have a heater and filter thermometer and a ammonia checking thingy

my Betta acts normally eats normally except i think he itches himself since he also has like discoloration patches in his body area but its not like ick or fuzzy or anything like that. im really worried help??