angelfish thoughts

Well- I sought advice for my angelfish on the planted tank forums, and was asked (of course) for water parameters and if there had been previous illness in the tank, and reminded "I dont think bacterial septicemia is something that a fish can "live with" for an extended amount of time. It is usually a late stage indication that the external bacteria has gone septic, which then leads to shutdown of internal organs... Once internal, it is very hard to bring this weakened fish back."

Tank temp 79-80
Ammonia- 0
Nitrite- 0
Nitrates- 10
pH 7.6

If it's some other kind of bacterial infection, will kanaplex continue to help? Checked back through my journal- I first saw the redness on the pectoral base back in January 2019, when I moved the fish her fins got caught in a net. I had forgotten about that! Don't recall any illness in the tank, but lots of fighting between the two angels- and they used to startle very easily and run into the walls...

If it's just an old physical injury, I suppose the best thing I can do is keep the tank cleaner. I feel bad it has been so long and never really healed. I had thought of and dismissed septicemia before, until I saw somewhere online that a person knew a fish that lived with it for years. Probably that wasn't what thgat other fish really had- and I shouldn't have doubted my first conclusion that this isn't it.