Stonefly sounds like your basic internal parasite, the magazine should also say something along the lines of mixed grazing helps reduce the cycle. Organic methods do work if applied properly, using mixed grazing, grass species, dry matter calculations,, being prepared to pay the money for regular fecal counts. There are so many if buts and maybes that its more intuition than science and that intution comes from experience.

Benjo, I have never heard of salmon poisoning but it sounds like an infected internal parasite to me. I assume the vet has doused her with wormer.