Paph leaf problem - Help!

[Orchid Whisperer]

As naoki suggested, it is quite possible that dipping the leaf in the chemical has caused toxicity, resulting in the leaf dying.

As jeremyinsf hinted, you dipped a sick leaf into the container, risking possible cross-contamination (possibly not just bacteria or fungi; a cut leaf could easily transmit a virus).

I would discard the remainder of that container. Buy new, fresh fungicide, use only as directed on the label.

[NYCorchidman]

I would love to see the photo of the leaf. Oh, well...

I think the best thing to do for a minor start of something like that is just to cut away the affected area, and then see if it comes back.

You want to buy the new container of that stuff and spray your plant following the instruction. undiluted is useless.
Give time, then if things are not getting better, you might want to try bactericide. again, follow the instruction and please dilute. lol

[kwarren]

Thank you for your input!

[JMLand]

I had similar issues with the same plant as well as a roth and a few others. What is your growing condition? In my case it turned out to be my swamp cooler. I had nothing in it to fight of fungus or bacteria and the air is was sending in to my gh was riddled with fungus. After adding bleach tabs to the water tank I didn't see any more spots form. Use phyton 27 to treat the existing spots and bam I was done.

[Gthumbz89]

I don't know if anyone has said this but cut deeper with a disinfected blade ( I use ethanol, or isopropyl) then sprinkle cinnamon onto the cut to staunch the wound (also an antibacterial) Then spray the whole plant with a product called physan 20 (be careful this stuff is really really strong kills everything!!!) If that doesn't kill your infection then you have yourself a kryptonian superbug infection

[kwarren]

Thank you both for your knowledge from personal experience. I just bought a small blowtorch and got a sharp blade red hot and cut off the infection. So far the cut shows no indication of carrying the infection further down the leaf (fingers crossed!) In the past I always dipped my cutting blade in alcohol in hopes that was enough.
Also, thanks so much to JMLand. Like you, I have a swamp cooler and never thought that it might be a source of fungus. This is very important info!. We had an unusually humid spring and early summer. I just stopped using my cooler for the season but will definitely use bleach tablets next year! Excellent info!
I have learned so much from this orchid board. A BIG THANK to all of you that go to the effort to give your expertise to less experienced growers such as myself. We appreciate it so much!!!