Sure, running a specific gravity of 1.009 works well for ich and also manages many species of flukes. It won’t help with velvet or Uronema.I guess my last question would be hyposalinity ?
Here is my post on that:
Hyposalinity
Hyposalinity Jay Hemdal 2021 This term refers to a long-term bath treatment for marine fishes in which the salt content of the water is lowered and held below the point that certain parasites can survive. The salt level reached, and the time of the treatment are the two variables...
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Jay