some observations on salt treatments:
3% salt
I used 3 teaspoons per 1 gallon of water or 7.5 pounds of salt per 150 gallons.
Very effective against Fish Lice and Epistylus. Bad guys are GONE.
That 3% salt level was safe for:
Puffers,
Severums, Dempseys and similar cichlids,
Trinidad Pleco, Gibbiceps Pleco (1 Gibb died but 5 lived so I claim coincidence),
Goldfish and Koi.
(5 out of 7 Trapdoor Snails died but I suspect Dimilin more than the salt, not sure there.)
I heard about 3% salt years ago from the Japanese dealers, and I was foolish to not understand, they were treating for Lice, not Ick.
Then I saw a video by a Canadian (Canada does not allow most if any fish medicines)
who used the 3% salt on Goldfish with Lice and dawn broke over marble head.
One thing we have had bad results on is just dumping the salt in the tank all at once.
(I've had more than 1 catfish shock out and die.)
2% Salt will kill ick.
Any salt treatment on almost all freshwater should be diluted 70% or more within 11 days.