>managed to kill a couple of corals in my paranioa<
You know what they say.....'may destroy ya'
But I understand the paranoia. I suffered from some of it when I saw the Montipora nudis in my frag tank. Even though I never saw anything in my main tank I started to freak and dipped some monster colonies in the Betadine solution. Eventually I calmed down when I realized there were none in the main tank.
Lugols solution .... from Wikepedia:
It consists of 5% iodine (I2) and 10% potassium iodide (KI) in distilled water with total iodine content of 130 mg/mL. Potassium iodide is added to render the iodine water-soluble. This solution is also used as an indicator to test for the presence of starches in organic compounds (turns a dark-blue/black).
Povidone Iodine (I think Betadine is just a trade name) - my bottle says 10% - has citric acid (buffer to control pH), sodium citrate (more buffer), disodium phosphate (more buffer), glycerin (makes it slippery,

), and Tween 80 (a surfactant, or kind of like a detergent, makes the solution foam more than Lugols. When I started using the stuff I used the super scientific method of eye balling the usual 15 drops per liter Lugol's dip and adding enough of the Betadine until the water was about the same shade of brown!