Hello all,This is my first summer season on my pond build I've posted pictures in my pond section to show my pond .I am a fairly new to keeping fish and still learning . I hear about 20% water changes (how often & why). Adding salt to the water ( what type how much )
Flukes , scraping fish etc . I have around 30 fish in my pond mixture of koi small mainly but one large Israeli around 14 inches and he grass carp and the rest are goldfish and shubunkins . The large Israeli is starting to flash and jump now and again but feeds like a mad .
Iam intrigued if there are things I should be doing this time of year to maintain good water quality .I've tested the water quite recently and everything was perfect .any suggestions would be great

Thanks.

I didn't find the right solution from the internet.

References:

- https://www.pond-life.me.uk/forum/viewtopic.php?f=27&t=16390

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