Any one know what could be wrong, suddenly tonight sticking to the surface, gils clamped shut and not really got a lot of life in it

Whitespot? Have you had any new additions or stress in the pond

Hi thanks for replying, no new koi for 5 years and I treated pond for blanket weed with ClearWaters Blanket Weed Treatment yesterday.

Common sense points to a reaction to the blanketweed treatment.Did the fish display any symptoms before trearment .Ive had fish flick with cloverleaf blanket answer,but not struggling like that.Your fish seems to have whitespot like symptoms and a salt like substance on its skin.Have you a microscope.