I'm currently in the same boat (thread's on Arowana forum) - previously dropped eye went cloudy, then the other eye's now clouding. No access to water test locally (even through what passes for shop). Making 25% changes every 2days, added sea-salt & almond leaves. No notable improvement...
Contemplating dispatching a few swordtails to stuff with antibiotics as she (aro) hand-feeds pretty easily... if/when she can see it.
At least my girl's still active & eating and apparently otherwise healthy. Her tank-mates are pretty low-key, so no stress that way. She's been missing shrimp bits to the SD's over the last couple of days, suggesting the cloud is starting to really impact vision.