They might get a little soggy and won't taste the best, flavor blasted or original?
Ohhh, live ones not the real snacks...
Should work
Nope, no contest
I can't really input on what material, since haven't built ma' Koi pond.
If you handle them a lot they should do that for a long time
kinda like ma' Phoebe (chicken in avatar) they may change they way they cuddle like sleeping to roosting