My tank was cycled for about 2 months. I then bought a sailfin tang and a vlamingi tang from one owner who had them for 4 years. Both are healthy (or at least thats what the owner siad). I didnt quarantine them because they are my first fishes in the tank. Its been a week and now I see the sailfin twitching (no flashing). It only does it maybe once every 5 mins or so. Does it have fluke? Should I treat with prazipro or potassium permanganate?