Koi acting strangely

All of the sudden alll of the koi in my pond are sitting on the bottom. Very much like they do in winter. 2 of my fish last week developed small red dots (about the size of a pencil eraser. so i salted and added fluke tabs; i also began feeding medikoi to all of them. Did a 20% water change after 48 hrs (last monday) and did another water change yesterday afternoon (no more salt added during the water changes). I checked water parameters and they look good. Am-0, Nit-0, pH-6.5; temp-80 deg F, pond is ~1,000 gallons, 40 gallon biofilter, and i have 10 fish, ranging from 6" to about 15". why are they acting this way? Any insight would be appreciated

Sounds to me like a predator injured 2 of them and now they are hiding.

generally, how long should i expect them to act this way? they dont even come up to feed when im standing there. they are really spooked.

It can take weeks. It is hard to determine how traumatized they are.

mine still wont come out from under there bridge .... ive taken to feeding them just as it starts to get dark ... they were just leaving the food all day ... they eat it then i sit and watch from a distance ... this has been going on for weeks .. but not to worried as they seem well and the water is good now .... think its just a mater of time ... hopefully yours will come round quicker than mine :icon_smile:

ok, thanks for the insight. Im new here and really appreciate the help!!