I have never seen or read that Vorticella will infect fish. I think the fish slime layer prevents the attachment of Vorticella stem. In the link below it has some detailed fish parasite information. Vorticella are not mentioned in the Peritrichs section. Peritrichs are a group composed of two main forms those with contractile and non-contractile stems. Voricella belong to the contractile forms. Are you sure growth was Vorticella and not the non-contactile species of Charchesium, Epistylis or Opercularia?
https://www.int-res.com/articles/feature/d070p001.pdf

Last edited by Bill Cody; 12/06/21 07:57 PM.

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