This may be a long post, but here we go....
1. Go to your local welding supply shop and dish out $200.00 for an oxygen tank, regulator and your first tank of oxygen
2. Locate a good source for fish bags. Buy them in bulk (I usually buy 1000 for smaller bags 8x14, 250 for 1/6th square bottom bags for larger fish) cost between $80 - $100.00. Also get some bag buddies or comparable additive for the shipping water.
3. Find a LFS willing to sell you shipping styros or get an account with a company that produces them for fish farms.
4. Go to your local sporting good shop and buy heat packs. The 40 hour ones are the best in case an overnight shipment gets delayed.
5. Get an account with a shipper. These vary. I currently use Airborne Express, but am in the process of setting up an account with Southwest Airlines. I have to have an airline rep come to our facility to prove I am legit (fallout from the 9/11 ordeal)
You can ship through the USPS, but they don't guarantee live animals and you can't tell them it's fish. Same thing with UPS and FedEx since the USPS and FedEx have merged.
These are the necessary things to have to ship fish.
Now how to do it......
Take a fish bag and fill it 1/3rd of the way with water from the tank of fish being shipped.
Place the fish in the bag of water keeping in mind you should only put so many fish per bag (this will be determined by the species, size of fish, size of bag and destination the shipment is going to.
After placing the fish in the bag of water, fill the bag with 2/3rds oxygen from your newly purchased oxygen tank (You may also want to add some bag buddies for extra measure).
Rubberband or tie off the bag. Place bag in shipping styro. Continue the above process until all fish are bagged that are going out in that shipment.
Take box to shipper with airway bill filled out and drop it off. Oh yah...don't forget to pay the shipping fee's.
Sound like a lot of work? It is, but after awhile it becomes second nature.
I posted this in this way for a practical reason....I have had a lot of people inquire about our fish, until they hear what shipping costs. They then ask why I charge for shipping.
The only extras I charge for (over and above the shipping costs) are for the shipping boxes which I have to buy and the heat packs which I also have to buy.
So you see shippers rarely break even on the process.
I really do not want to discourage anyone from attempting to ship fish, but in order to do it right and ensure safe and live arrival it has to be done properly.
HTH