I would give it a try in a plant only tank and monitor what happens. If all the parameters of a healthy tank remain in place then put some white clouds in and see if they can stay healthy and not pick up any parasites. If having done all this and putting new dung in while the fish are in and no parasites then Id' start to think there may be something to all this. Of course for it to mean anything though I'd like a side by side comparison with another tank without any dung added.
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