does anyone know what causes this???? i have heard so many theories like bad handling of fish,quality of water,temperature etc is it safe to eat these fish and handle them???

I think it is probably caused by handling with dry hands whereby the mucus coating over the scales is rubbed off, it can also happen with wet hands if the fishh is handled a bit roughly. As far as eating is concerned I would have resevations about it because this is only my opinion it could be an infection perhaps some one else can give a more experienced opinion.

Alan

Hi peekaboo

Saprolegina is the most likely candidate you are describing.

This is a fungal infection that is stress related in its outbreak. In so much that if a fish is healthy and stress free then even though sapro spores may be present it does not infect the fish.
Fish DO stress at water temp/oxygen change, bad handling and spawning (and a whole host of reasons) so it can be one, or many factors involved in an outbreak and with badly dropped immune systems comes the greater probability of death.
The overcrowding of fish in rearing tanks and movement usually gets the blame as this causes many stresses .
The problem WAS addressed by the use of a bath in a solution of 'malachite green'(cupric) which killed the fungus after but a few seconds of contact.
This chemical has now been withdrawn(circa mid 90's), even for use on cyprinids, as there is a chance that there is contact with human food chain.

Is it safe to eat......why not?.....just make sure your mashed potatoes are as light and fluffy as sapro then lean the fish into the mash in the infected area

Note: I'm fairly sure that this fungi is non hallucinogenic.....cook it well

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