Angles out of the QT

MY two medium size angles are out of the QT tank with Maracyn after suffering from a bout of rot, brought on initially by an attack from a community Betta (now separated) and previously high PH 8.0. (IMO). However I must admit that neither of the other two juvenile angles were affected by rot and of course were never attacked. Funny how fin nipping can bring out rot. Anyway they are both out a day early after responding so well but I hope not so early that rot returns. Although I realize that rot is not contagious, having the UV sterilizer on the last week has seemed to help as each angel was treated in turn. When I placed the first angle in the QT I also turned on my community tank UV sterilizer. While the first angle in the QT with meds lost all symptoms (white puffs and lines on fins), the affected areas also fell away or disintegrated leaving it with a much shorter Caudal fin. In the mean time the 2nd angle left in the community tank with the UV sterilizer ruining lost all symptoms as weill the next day but with no further deterioration and after the 2nd angles turn in the QT tank 90% of his caudal remains while the other was left with only 20% although both initial had about the same severity of rot. Perhaps there was more in the water in the way of free floating organisms that affected the rot then I realized. Now I make sure I turn on the sterilizer every evening for at least 12 hours a day. Incidentally my water parameters were all well within good range toxins-0, nitrates-10, PH 7.8-8 (too high IMO). Iv since got my PH back down to 7.4. And hope in the near future with changing over to potassium water softener filtration to get it down to 7.2-7.0. without the use of chemicals.

Yes Iv heard and read about the problems with unmatched UV sterilizers paired with pumps with too much GPH. Mine is a matched system 24W UV sterilizer with matched integrated low GPH pump and spiral flow for the correct engineered rate of UV exposure for maximum chromosome damage to organisms. I'm able to have my 60 tank directly across from a window that I use to bring in daytime light instead also a side windows louvers in sun light for my 120. On top of this my API phosphate reading are 5-10 (dark blue). But I’m convinced from Personal experience that the "UV Green Killing machine" really works in spite of these bloom contributing factors. As a result my aquariums have been crystal clear since I started using the Green Killing machine and IMO helped kill bacteria that can attack my fish wheather fin or disease. But this is just my personal experience, Im not making any authoritative claims here.