I guess this thread has run its course unless sickness reappears. I will close it out now with a few pics. One day I’ll start a showcase thread. Thanks for the help.
Conclusion:
Fish are doing great now only a very few with red streaks. Glad now I did the Fish Vet route. That stopped me with going crazy with pond poison meds. I have 1 litre of formalin for sale lol.
I addressed all the possibilities of problems that the Vet report showed. All except for I didn’t treat for any sickness

One of her suggestions was fish stress by environmental factors. So here is what I did.
Chlorine Chloramine: Possible toxicity as I was a little lax about adding in de-chlorinator. Treated entire pond. Test is 0.
Fertilizer: Some got in when I was watering shrubs, flowers on pond edge. Did partial water change.
Aeration: Possible lower levels o2 due to algae problem. Added 4 more aeration spots.
Algae: Overload of string algae on waterfall and in pond. Removed it and plugged in a UV light with Keeping salt at .1 %. to deal with green water algae.
Filtration: Increased filter media and will clean them more often.
pH: Tested high at 8.8. I don’t think so as my tests and PetSmart had it at 7.6. Got a drop test instead of strips. pH tested now 7.5 to 8.
Food: Cut down on feeding quantity. Still feeding Hikari staple. I am not one of those that doesn’t ever feed fish and let them eat pond grud, not good for koi IMO.
Petsmart: I guess it’s environmental and not sick fish. If illness reappears after all the upgrades I did then it’s possible sick
PetSmart
fish. For now Sorry PetSmart.