Kordon ® Breathing Bags™ are a fantastic way of transporting guppies, especially when a flight or extended time is necessary.
The technology was first developed in space/military research and was refined to produce the bags that we have today by Kordon together with plastics & chemical engineers.
The Breathing Bags allow the transfer of gas molecules through the plastic wall of the bag, carbon dioxide and oxygen in particular. As long as there is a breathable atmosphere outside the Breathing Bag, the guppies inside will not run out of oxygen.
Carbon dioxide exits the bags at 4 times the rate oxygen enters the bags, thereby constantly purging the water of toxic carbon dioxide and allowing oxygen to replace it in the water.
Prior to this invention, the only bags available for shipping guppies were made of ordinary polyethylene. When using these "barrier" bags, oxygen must be added as a gas inside the bag prior to sealing and shipment. However, this process has many problems including:
a, high concentrations of oxygen can cause flammable conditions,
b, the presence of oxygen gas inside the bag takes up a lot of valuable shipping space,
c, once the supplied oxygen is used up there is no more available,
d, toxic carbon dioxide from the fishes' breathing builds up in the water, displacing the oxygen
e, the oxygenated air in the bags may not be satisfactory for fishes' breathing, because the bottled oxygen can be contaminated,
f, a bag partially full of water with the rest filled with oxygen allows the contents to slosh during transport, stressing fishes.
After adding water and a guppy to the Breathing Bag, seal the bag with no airspace. I prefer to do this with a knot rather than with an elastic band. Breathing bags can be sealed using all of the current methods: rubber bands, twist ties, metal clips, etc.
Guppies adapt readily to the lack of an airspace and so an airspace is not needed. It is best if there is no air pocket in the bag so that there is no water movement, keeping the fishes calmer with less stress. An unneeded air space also uses up valuable shipping space.
Breathing Bags function well when packed in conventional Polystyrine or cardboard boxes. These boxes have a high rate of breathability, even if these containers are sealed with tape. Air is normally over 21% oxygen, which is over 210,000 ppm (parts per million). Aquatic invertebrates and fishes normally have only about 4-14 ppm oxygen available to them in water.
It takes only a small amount of air passing through the packaging materials to sufficiently oxygenate the water in the Breathing Bags. This is even true for shipping boxes in an air cargo space that is not pressurized. There is sufficient oxygen at higher altitudes for the aquatic life in the Breathing Bags.
Higher temperatures increase the "breathability" of the bags, the rate at which oxygen and carbon dioxide is exchanged.
When packing individual bags in shipping boxes, it is best to separate each bag, such as with flat pieces of corrugated cardboard or layers of newspaper, wrapping paper etc so that as much bag surface area as possible is exposed to the air in the shipping container. These materials are completely porous to air and oxygen.
Breathing Bags should not be shipped inside a "barrier" type plastic liner bag. The barrier effect of the outer non-breathing bag will prevent the Breathing Bags from performing properly.
During tests, fishes, both freshwater and marine, have survived for one month and more in shipment, including on successive flights and land transportation. However this is no excuse for extended periods of containment in the breathable bags and as with every transportation of guppies the journey time should be kept to a minimum.