Emergency - Breather Bags and Cories

[Deb]

As some of you may remember, I have been trying to get C. habrosus for quite some time, and now it looks like a friend can ship a couple to me.

He usually uses Breather Bags to ship fish.
He has not shipped cories before.
Breather Bags are not made to be used with Bettas and other air breathing fish.

I know cories often go up to the surface for a gulp of air. Do they need to be able to do this in a shipping bag?
I need to know ASAP because my friend can ship later this week, when he picks up the fish.

Any help at all would be great, if you are familar with these bags.

Thank you !!!

Deb

[syno321]

I wouldn't use the breather bags for 2 reasons. 1) the corys do need to breathe atmospheric air and would probably suffer if denied access to the surface. 2) I'm not sure how the breather bags would stand up to the corys dorsal and pectoral spines and so I wouldn't take the chance. In my considerable experience I've always shipped corys in 1/3 water, 2/3 air, doubled bagged (so they don't pierce the bag)and never experienced any problems.

[pturley]

Corydoras and breather bags definately DO NOT MIX!

Tell him to stop in at the LFS and get some standard fish bags and ship them with over 80-90% filled with air (BTW: NOT O2!).

[Deb]

Thanks, Syno321 and Paul. I had a feeling the answer would be "no", and that's good because everyone's in agreement on this one.

I'll ask him to ship them the way you have described, Paul. Thanks again.

Deb

[Mike_Noren]

Corydoras and breather bags definately DO NOT MIX!

I know breathing bags are usually filled completely full, as they take their O2 from the surrounding and filling them gives maximum water volume, but AFAI can see there's nothing stopping him from filling it to only 2/3rds or so... The O2 will diffuse in to the bag just fine anyway.

[Deb]

Thanks for your input, Mike.
But I'm inclined now to go with the regular poly bags, and my friend that's shipping them wants to go that route, too.

Paul, we are all curious about your O2 warning.
Is pure O2 just too rich for cories, and it's not what we breathe anyway?

Deb

[MatsP]

Thanks for your input, Mike.
But I'm inclined now to go with the regular poly bags, and my friend that's shipping them wants to go that route, too.

Paul, we are all curious about your O2 warning.
Is pure O2 just too rich for cories, and it's not what we breathe anyway?

Deb

I'm not Paul, but I'd be inclined to saying that breathing pure O2 (or nearly pure, because it's unlikely that anyone will get ALL the air out of the bag before pushing O2 in there) will not be particularly good.

There's 21% O2 in the air, the rest is mostly nitrogen (N2) at 78%, with a few tenths of various other things, such as CO2 and H20, with small proportions of all sorts of other components.

--
Mats

[syno321]

Just as pure oxygen will burn the breathing organs of labrynth fish, it will have detrimental effect on other air breathing fish, as many catfish species are. Their evolutionary advantage allows them to breathe atmospheric air when other fish are dying, so why not let them.

[ErickJones]

, but AFAI can see there's nothing stopping him from filling it to only 2/3rds or so... The O2 will diffuse in to the bag just fine anyway.

If you leave an air gap in a breather bag, the bag will collapse as the air exites through the bag. leaving you with a colapsed bag. They are meant to be completely filled with water. and I while I like breather bags for shipping I wouldn't use them for catfish period the spines will shred the bag and doubling the bags seems to inhibit the o2 exchange. jmtb

[Mike_Noren]

If you leave an air gap in a breather bag, the bag will collapse as the air exites through the bag. leaving you with a colapsed bag.

Hmmm... Are you sure about this? I was under the impression nitrogen gas couldn't pass through a breathing bag?

I've never shipped fish in partially filled breathing bags, but I have had fish stored for about 8 hours in partially filled breathing bags, and while they didn't collapse it is possible the volume of air in them decreased, I do not know.

Looking at: http://www.novalek.com/kpd74.htm
I get the impression you can partially fill breathing bags, but that it is not desirable because the water will slosh around and stress the fish.

As this is of more than theoretical interest to me, I'll do an experiment and let you know what happens.

[Deb]

Thanks, Syno, Mats, and all.

I'm going to use the double-bagging, and air space ideas suggested by Syno and Paul. I've told the guy who's shipping to leave a large air space - about 80%.

Deb