Opinions on breathing bags

[croaker]

I'm curious what people in the industry think of breathing bags...are they better than regular bags with O2? or just something that's a pain because of more weight with the extra water that is needed with them? or what? Are they popular in shipments from say Hawaii or something?

Thanks for the info!

 

[PeterIMA]

Breathing bags have a membrane originally developed by the Russian space program. I have conducted experiments with these bags (which come in 3 sizes and also a liner bag). The bag can be completely filled without air. Provided the surface is in contact with paper or stryrofoam (not a wet surface) they will exchange carbon dioxide excreted by fish in the bag for oxygen outside the bag. Air can be exchanged through styrofoam box walls. However, if you pack them inside a stryrofoam box with a liner bag (even a breathing liner) the ability to exchange oxygen is markedly reduced. The bags are sold by Kordon, and Dr. Rofen has a paper concerning their use for transporting freshwater fishes.

I have kept marine fish alive in the bags for more than 80 hours with good results (low mortality). One clownfish was kept alive in a breathing bag for three weeks.

Some of the problems is that they have a thin membrane and fish with spines or sharp teeth can rupture the breathing bags. There are some means around this problem, but more research is needed before I would use them to ship marine tropical fish from overseas.

My understanding is they are being used to ship live brine shrimp to customers in North America. I would be interested in hearing about the experiences of others who have used the bags.

Peter Rubec

 

[croaker]

Thanks Peter for the reply. It seems like they would be great and the price is a little higher than normal poly bags, but if no oxygen is needed to add to the bags, maybe it evens out? Live brine I bet would do great in these bags. Do you happen to know the company that was using them? I wonder if anyone uses them for shipping invertebrates like snails etc.? I would be interested in other's opinions as well.

 

[PeterIMA]

Croaker, I am not sure what you meant about "if no oxygen is needed to add to the bags, maybe it evens out?". You might be implying that more bags could be packed in a styrofoam box because less space is needed with the breathing bags. However, this would make the box very heavy and is not advisable.

The main advantage of breathing bags is the fish survive longer and are not as stressed. So, they are still worth using for shipping fishes without spines (either freshwater or marine). But, one needs to still pack them in a box with a liner bag to keep the box from leaking on the airplane.

They certainly have utility for hobbyists transporting a few fish to a conference etc. They could be used for shipping marine invertebrates as you suggested.

Peter

 

[croaker]

Sorry Peter. I meant that the cost of the breathing bags vs. regular bags plus the cost of getting the oxygen cylinder might even out, if one uses a lot of oxygen. I don't really know the cost to get/rent an O2 cylinder but it seems like it would be one less expense. I hope that was clearer.

Thanks for your help Peter!

Anyone else?