I mainly use FedEx boxes, 11x11, 14x14 and 16x16, for Southwest I use my import boxes, already have styrofoam in the boxes. I don't use spray foam; it's not needed to fill the cracks. In the winter, I use the styro with newspaper, cardboard paper, blankets from the exporter shipments, poly, etc. and several heat packs with a hole cut in the top piece of the lid to let oxygen in to keep the heat packs going. In the summer I do the same hole but it's to help make sure the box doesn't overheat should the box be left outside in direct sunlight, etc. I use oxygen that I get from the local welding store. I always use more oxygen than water, never know when there will be a delay so always use the biggest bag possible. If I have one small fish like 3" for example, it will go out in an 11x11, and I will use the biggest bag possible to fill up all the space. Sometimes I have a little smaller but the rates I get, I can use 11x11 for the same price as a smaller box and up to 16x16. Rarely do I have a Doa, but it happens with everyone due to weather, delays, handling of the box, stressed fish, etc. I've shipped stingrays to Alaska on a 4 day delayed FedEx trip and arrived perfect, same for the golden fire eel, but I shipped 4 Zebra plecos to Toledo, several hours from me and they all but one were DOA, make no sense sometimes. I shipped some fish to Hawaii, 2 day trip due to their inspections and the fish was fine. I also don't use Prime or any other additives. Fish are purged depending on their size from 4 days to 2 weeks and I do a water change on their tanks the day before. I never use tap water, I use 100% tank water to ship the fish in. You don't want to use water with different water parameters into the fish that is being shipped.
