Finding multiple fish species and including marron, it suggests an environmental/toxic cause is likely (instead of infectious). Let’s see what authorities find as the cause.
http://mobile.abc.net.au/news/2015-02-03/thousands-of-fish-dead-in-collie-river/6064558
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Yours sincerely,
Dr Richmond Loh
DipProjMgt, BSc, BVMS, MPhil (Pathology) Murdoch, MANZCVS (Aquatics& Pathobiology), CertAqV, CMAVA, NATA Signatory.
THE FISH VET, Perth, Western Australia.
Veterinary Medicine for fish.
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