Re: [RML] Breathable bags

Bruce Hansen (bhansen at
Mon, 9 Dec 1996 14:27:33 +1000

Roy left us a few of the Kordon bags to plkay with but I have been unable
to find a situation when they would be ideally suited.

On the surface a good Idea but in practice?

BTW I seem to remember that Heiko was a proponent of full (of water that
is) bags
but was laughed at by the audience when he presented the idea at a talk he
gave ?at an Aquarama a few years ago - I am not sure if they had these bags

Bruce Hansen

> From: Gary Lange <gwlange at>
> To: rainbowfish list <rainbowfish at>
> Subject: [RML] Breathable bags
> Date: Saturday, 8 March 1997 14:43
> Has anyone actually used the Kordon breathing bags in any sort of
> field conditions? I thought the bags sounded like a good idea and
> have used them successfully in "hotel" conditions for 5 days in a
> completely filled bag but I really have my doubts about using them
> for either shipping or for collecting.
> For those that are not familiar with the item it is an extremely thin
> walled bag about 1/2 the thickness of the cheap pet store bags & 1/4
> the thickness of the bags that we normally associated with "box" bags
> or fairly large type shipping bags. I had two nice 3 inch siamese
> algae eaters that I kept alive this way for 5 days when I was on a
> trip. I really watched them closely for the first hour because
> "everyone" knows except the newbie or the no-hoper that you have 1/4
> water and 3/4 air in your bags or some fairly low ratio like that.
> The instructions on these bags are to fill them up to the very top.
> The CO2 and O2 is exchanged through the pores in the bags (from the
> water to the air, not air to air or water to water) . One problem is
> that if the bag is wet on the outside this exchange really can't take
> place. People that try and float the bags will cut off most of the
> exchange as stated by the manufacturer. If you double bag you have
> to make sure that you don't get any water in between the two bags,
> otherwise you get the same effect.
> Although the fish won't slosh around much in a completely full bag
> they also weigh alot more which isn't much fun to either pay for or
> carry around. Also a styro stuffed with bags, all filled with water
> might have a tough time exchanging air anyway. There are certainly
> some times that these bags are great to have around but I don't think
> that they will be as useful as once thought. I would imagine that
> they have to be this thin because thicker bags won't breath enough
> otherwise.
> Gary Lange
> Rainbowfish Study Group of NA