Hello ladies and gents.
I have a 13.5" Silver Arowana by itself in a temporary 55g tank since I'm preparing a 210g tank. For three week now I'm battling eye sickness with my aro, both eyes have white slimy coat. What I have done: two times a week 30-50% water change, Melafix every day, two time a week feeding, 86F constant temp. After first week here was much less slime on both eyes but a few days later it creeped back. I kept medicating and changing water as I stated above , week and a half later slime was almost all gone. Yeasterday slime started to come back again.
As sickness started my aro refused its regular food - ff shrimp and only eats live feeders. Feeders are clean since I feed my oscars same feeders and all is good.
Equipment running he tank: Rena XP4, Aqueon 150W heater, 2 nozzle air pump with 2 12" airstones, 9W UV filter.
Am I doing something wrong? Is there any other better treatments, medications?
As I said, I am preparing to upgrade to a 210g tank but I have to dismantle a 55g arowana tank and 110g Oscar tank. Temporarily moving oscars is not a problem but I assume moving a sick aro could end in a disaster. Any tips what's the best way to move my aro? Should I wait for it to fully recover and then some before moving it? Is there a chance this sickness can come back due to moving stress?

P.S. Aro is very active, has great colors and fins and shows no other signs of sickness other than white slime on eyes. No pic because my aro is scared of a camera and starts going wild as soon as she sees it.