Here is a post I made on my most recent online purchase.
I took pics of how it was packaged.
I will also explain how it was packaged.
Their was a box cardbord that was very heavly taped all the seams where taped.
Inside this was a styrofoam box with lid that fix perfectly inside the cardbord box. All the seams around the lid of this box where taped aswell.
Inside this box are heating pads/cooling pads if its hot/cold when it ships. Items shipped now in the states would most certenly have a few heat packs to help keep the temp from dropping to much.
Each bag was tripple bagged with a dark thicker plastic cup like thing between two of the bags where the fish sat.
Each bag had only 1 fish and if it had 2 the bag was much larger than a single fish bag.
From my understanding the bags are shipped and oxygen is injected into the bags jst prior to tieing them shut so as to maintain oxygen levels durring shippment.
All the bags where placed so they did not shift durring transport. In my case there was a small baggie of water added as fillter.
That should get you alot of the basics.