Too many variables to really diagnose. I would remove anything and stop introducing anything from the wild. I would restart lives foods from scratch using sterile equipment and clean sources.
I would treat for parasites and bacterial infections. I would do an external round for parasites and then orally treat for bacterial infections. After that I would treat for parasites internally.
Paracleanse or PraziPro for external.
Kanaplex for bacterial infection via food.
Metroplex for internal parasites via food.
Personally, and I mean I would not recommend this, but I would do it myself. I would dose PraziPro and feed Kanaplex simultaneously. Rest them for a week and then hit with metroplex. I would watch, if I saw any flashing, I would do a 4 week course of PraziPro. But again, that's me.