So, almost a month gone by. I moved most of the fish from my pool back into the pond today.
The only two I did not I am somewhat concerned about.
One somewhat largish colorless goldfish (I do not think I have ever bought one like this, but since I read they change color as life goes on, perhaps it must have had red spots on the back, but not anymore - totally colorless now.) This one has red inflammation in fins, part of body and some sort of a strange bump near the mouth (it used to be much more inflamed before, but still does not look good). I imagine this is some sort of bacterial infection? I fed all fish for 5 days with food combined with Maracyn2, and then for a week with food with Maracyn (the results have been positive on other fish, another largish goldfish I have does not have any blood streaks on its fins). I also tried to treat the bump and other inflamed areas with bio-bandage. When I got it from the pond, I removed like 5-6 anchor worms from it and there were some ulcer spots where anchor worms already detached, I guess.
Not sure what to do next, another round of antibiotics? It's eating (at least it used to show up with all other fish at the feeding time) and I can't say it's inactive.
The other one is a koi, about a week after relocation into the pool I was inspecting fish there and noticed this one did not have dorsal fin at all, just two bones sticking out, huh? It was not the case of finrot, I think, I never saw any growth or anything. The fish is pretty active, comes for food and such. I tried to apply biobandage whenever I can catch it (not frequently), and the situation does not seem to improve. I wonder what next steps can I take here?
BTW, speaking of the pond, fun thing has happened, after I refilled it back with water a month ago, I poured in like 1/2 gal of 20% (? or was it 10%?) household ammonia in there, once the ammonia was consumed by bacteria in the filter in about a week, in three more days algae bloom (that started like 2 days in after filling) started to clear and the water turned to be crystal clear (and still remains) even before I had a chance to activate UV filters. I guess there is some truth in the research that some of the ammonia-consuming bacteria also targets algae when it's starving.