Advice needed for Albino Catfish

[Leonardo]

hey all, I got a 4incher white/albino red tail catfish aweek ago.
the problem i'm facing now is that this little beauty had not eaten anything at all and she's getting skinnier and skinnier... from my experience with catfishes, the moment you put them into a tank, they'll start wacking anything and everything, atleast most would.

it was in my new project "Albino Comm Tank".
Now it's in a small hospital tank...
I've tried all kinds of food but it don't even touch it. .
thought it needed time to acclamatize, or be more stable but it's taking too long an losing lotsa mass...
water wise all good.... tried all i know but in vain.

I'm worried now that it'll starve to death.
how long can a catfish go without food?
any advice for it to start eating?
TIA!!