Dead fish

[kentjames]

I would be looking in the bottom of the pond ,something odd there with the bubbles coming up

 

That would be an air stone connected to an air pump / compressor...

 

I used to be in Koi ponds and koi carp etc and still keep koi so I take with experience.

 

It could be anaerobic sludge being stirred up from the bottom or the aforementioned substance that david has mentioned.

 

I would highly recommend a series of 20% water changes and a very good dose of Watersafe by Tetrapond - this primarily removes chlorine and chloramines but does have a very good effect on removing excessive metals and contaminants.

 

Be cautious of large temp changes through excessive water changes, if no purifier is available then spray the water into the pond to help gas off the chlorine - this wont work on the chloramines but will help.

 

James

[Stephen Blair]

The pond could be full of these

soapfish - Google Search

[charlie6]

The chlorine is best out of the water before going into the pond.

[kev7937]

Thanks for the replies on this, I'm inclined to go with the aesculin poisoning as I think the foam did have a bluey tinge as A hippo does when chipping on a wet day and have found a couple of references like the Cherokee one.

 

I will certainly be recommending a gradual water change before restocking but its probably best they get a pro in before spending on any fish.