Help save my Davinci Clown!

[Rpetersen]

Hey friends,

3 days ago I purchased two clownfish from my local fish store (J & L aquatics) here in Vancouver, Canada. Great store. I bought one intermediate-sized Davinci clown and a smaller black Percula. I observed both at the pet store for a week - both striking physically and behaviorally super active.

The small clown is thriving. The larger female is struggling. 75% of the time she's on the bottom of my QT tank, struggling seemingly to get lift and maintain an upright position. She has not eaten. Her colors are still striking - no signs of ich or velvet or flukes. Every now and then she bolts around the tank, but this is becoming more and more infrequent.

pH is 8.2, temp is 77 F, ammonia is 0, nitrite is 0, nitrate is 5, and salinity is 1.022 (my fish store was at 1.024 so I drip acclimated for ~2 hrs). The store water had no traceable ammonia via Red Sea test kit (which is working great as I cycled my QT tank and initially it was sky high).

I'm thinking it is a swim bladder problem. Likely an infection, posssibly a parasite? My problem: I only have Cupramine on hand. Prazipro is on the way. Canada has banned all antibacterials etc. so getting some Seachem metroplex/focus is tricky. I am a chemist, however, and have access to things like methylene blue and potassium permanganate. No idea though what is best for this...

What would you do? This fish is too beautiful (and pricey) to let slide. It's possible I'm being totally played... but highly unlikely as she's often laying completely flat and has mildly-appearing labored breathing.

Thanks for the help!