Need help identifying a piece of classical music

[ChickLittle]

I fully appreciate how difficult this will be on a website but...

I've got a piece of music in my head and I can't identify it. I believe it's most likely to be Tchaikovsky, or certainly that style. It features a piano (but isn't a piano concerto), some woodwind, possibly flute, and strings. It is ethereal sounding, with the strings/flute making long sweeping sounds while the piano plays quickly.

I must've heard it recently for it to have planted itself in my head so there's a chance it's featured on an advert or has been used on a tv programme.

I thought it was from a ballet but i've listened through snippets of Swan Lake, Sleeping Beauty and Nutcracker and not heard it.

If anyone has any ideas, or knows a site where you can identify music by humming it (don't think i'm close enough to the original to shazam it!) then i'd be very grateful.

[ChickLittle]

I always seem to find answers to my questions 5 minutes after posting on here - despite spending hours looking for it before posting!

It is Aquarium from Carnival of the Animals by Saint Saens.