I was told years ago that you can use Kosher salt from the grocery store for the tanks. This was from 2 different fish store owners. I have been doing this for years without issues. I have been out of salt for awhile *finally found it at a different store* but everyone seems fine either way. I have goldies, bettas, black mollies, guppies, gold severums, gouramis, plecos, angels and a few more. I used it also for my old ciclid tank as well with no issues. Just my experiences.