i received my order yesterday from this site. i was 15 degrees when it arrived. the heat packs did the job, so far all are alive and doing well (crabs, shrimp, snails, feather dusters, some starfish, and a fish):cheer:
I also ordered from here in the winter - and it was deleivered in 2 degree weather with 3 heat packs - those little suckers were warmer them I was!
This is a good site and you can trust that they know when to use the heat packs
good luck and let us know how it works out for you