Not a fan of salting a pond, if that's what you mean. You have to mess with salinity levels, as the salt never actually leaves the pond, so when water evaporates, concentration increases. If you remove water from the pond in an effort to reduce the salt, you have to be careful how you dispose of it, as it can be less than beneficial in a garden for example, depending on the salinity level. And pond plants can struggle to grow in salted water.
As a treatment for an individual fish it has it's place. Salt can also kill parasites, but there is new evidence that suggests parasites are developing a resistance to salt, much like bacteria and antibiotics. So overuse - like full pond salting - can have a deleterious effect. We have only used a salt bath one time for a fish with hole in the head, but it worked beautifully. Healed up just in time for a skunk to come along and fish him out of the pond and devour him! Haha!
As a treatment for an individual fish it has it's place. Salt can also kill parasites, but there is new evidence that suggests parasites are developing a resistance to salt, much like bacteria and antibiotics. So overuse - like full pond salting - can have a deleterious effect. We have only used a salt bath one time for a fish with hole in the head, but it worked beautifully. Healed up just in time for a skunk to come along and fish him out of the pond and devour him! Haha!