Hi, Zeebo,
I feel so sorry for your fish, he looks really stressed....that is why his color has changed.
Methylen Blue if more for fungal infections, and for treating
nitrite poisening....I've never personally used it, but know Dino and CWC do, so they could give better advice there.
I do know Melafix is used in bacterial infections, and it MIGHT be a help, but can't say for sure, on popeye. I would say it wouldn't hurt.
Hopefully you are doing lots of water changes. Is this fish still eating?
I'm not familiar with the other medications you have listed. Other medications indicated for popeye though are Tetracycline, and Trisulfa. Both are available here in the US in pet stores. These will likely disrupt your
nitrogen cycle.
Any time you use medications with your fish, use the full recommended dosing, and be sure afterward to use carbon in your filter for 24 hours, to remove the medication, and keep an eye on your nitrogen cycle. Hope this helps....