Shipping of Corydoras: Coal or zeolite?

cartouche · Post by **cartouche** » 01 Jun 2006, 00:27

Hi, I have a big problem now. During the last three months I twice lost almost whole bags with big sterbai. At first I packed them by 3-4 pieces into one bag 22 cm (8,7 inch) wide and after I sold them, the customer reported that after 6 hours, 4 out of 11 were dead. I tested it at home, I laid a bag with 4 sterbai on the water surface in my tank, but after 6 hours they were all O.K., so I thought it was his fault. But later I took 2x7 sterbai and after 4 hours, all but 2 were dead.

I note that I have never shipped big sterbai before, only young fish. Some breeders told me that sterbai excrete some poisonous secretion when stressed, and it can kill them. But I still don't know, if it's actually true, although the case with the bag on the surface may support it. I rather suspect CH3 (ammonia), because the water was relatively alkaline (pH 7,5), and I didn't purge the fish properly before the way (they shouldn't be fed for 3-4 days at least, but I didn't feed them only 1,5 day before the shipment). The water was quite polluted, full of dirt and somewhat milky, when the fish were dying.

I was told that against the "poisonous secret" the best choice would be coal, but one expert told me that it takes oxygen away from the water and furthermore, it allegedly elevates ammonium in water. So I rather incline to use zeolite, because it works best against ammonia, but again, I don't know if it works against the mysterious "poisonous secret". Does anybody here have any idea about it?

Mike_Noren · Post by **Mike_Noren** » 01 Jun 2006, 00:43

cartouche wrote:I was told that against the "poisonous secret" the best choice would be coal, but one expert told me that it takes oxygen away from the water and furthermore, it allegedly elevates ammonium in water.

If the problem is some sort of toxin excreted by the fish, then yes, activated carbon would be best against that. It also does NOT deplete oxygen or increase ammonium.

So I rather incline to use zeolite, because it works best against ammonia, but again, I don't know if it works against the mysterious "poisonous secret".

Zeolite, working by ion exchange, should not help against an organic poison.

cartouche · Post by **cartouche** » 01 Jun 2006, 00:55

So, should I use coal+zeolite together???

Mike_Noren · Post by **Mike_Noren** » 01 Jun 2006, 08:06

If you want. The zeolite and the activated carbon shouldn't affect eachother.

Owch · Post by **Owch** » 01 Jun 2006, 11:16

Do you starve your fish for a couple of days before shipping?

Do you oxygenate your bags before shipping? (a squirt of pure oxygen in to the head space of the bag will do)

Do you add any nitrogenous waste absorber (I think amquel zaps this) to your bags before shipping?

That should help ship fish in bags and keep them alive. But being an experienced fish keeper and breeder, you should know that.

Tom

cartouche · Post by **cartouche** » 01 Jun 2006, 14:06

I think that one of the problems may have been just insufficient purging. As I said, I stopped feeding on Wednesday evening, and I took the fish on Friday morning. But what about the fish that survived in the bag in my tank for the same time? I made the same procedure with them and used the same water (from a rearing tank, one day after cleaning - maybe another fault, because I didn't measure nitrites then, not speaking about the presence of bacteria in the water).

But still, I would want to know if the rumours about the poison are based on reality (on some scientific data). I have heard it from various breeders, even from different countries. If it is true, then no nitrogenous waste absorber would help.

As for oxygen, no, I don't use it. I have heard that it may rather make more problems than solutions. The Corydoras can allegedly burn their gills. But it is true that if the oxygen is not too concentrated, then it should make no problems. However, I think that adding oxygen into bags with Corydoras is unecessary, unless the bags are heavily loaded with fish or transported for a long time (say, one day) - which is not my case. Moreover, I usually open the bags during the way to change the air in it, so suffocation has never been a problem in me. The problem is obviously in the water.

I have heard about Amquel recently from one American, but it's not available here. As I said, the ammonia should be removed by zeolite and the poison - if it exists at all - by coal.

And as for my experince, I transported only young fish during the last three years, and not too frequently, because I started to massly produce them as late as in the end of the last year. However, I have never had any problems with it, even if I transported relatively densely loaded bags for about 10 hours. The problems started in January this year, when the quality and chemistry of my tap water began to change (especially ammonia and pH has risen very markedly) - which is another reason, why I rather suspect ammonia than the mysterious "poison".

Post by **Coryman** » 01 Jun 2006, 14:28

There are quite a number of Corys that are prone to self poisoning, this is something I am sure they do not do intentionally, but more of a reaction from stress. It is more likely to happen with fish that have been well established in a tank and then for some reason or another they are put under stress. This also happens in traders tanks where fish have been in stock for a while and well settled. The normal procedure is that water is taken from the tank, put into a bag, the fish are usually caught fairly quickly and put into the bag. It is then that they start to react to the trauma and excrete a substance from their gill openings, whatever the substance is it has the same effect as suffocation. The first sign is a slight foaming on the surface and then a yellowing of the water. If this is not dealt with very quickly the fish die. The picture shows the female of this pair actually in the process of releasing the milky fluid from her gills.

The remedy is quite simple, first take water from the tank which the fish will be transported in, then either disturb the fish, basically frighten them a little to put then under stress. This will cause them to release the toxic fluid (this may actually be a natural defensive mechanism against predation), then after a few minutes the fish can be caught and put into the transporting bag/s. The other way would be to again collect the good water for transporting and then put some tank water into a small container catch and put the fish in there for a few minutes to give them time to react to being caught, then re-catch the fish and put them into the bag.

With regard to putting neat oxygen into the bag, for me this is a no no, Corys come to the surface to take a gulp of air, which they swallow, this acts to aid buoyancy but the fish also absorbs the oxygen from it through the gut. Taking pure oxygen can inflame the gut and cause secondary bacterial infections, the first signs are the infamous red blotches in the belly.

Ian

bronzefry · Post by **bronzefry** » 01 Jun 2006, 15:47

Is alarm substance (Schreckstoff) a more likely culprit?
Amanda

MatsP · Post by **MatsP** » 01 Jun 2006, 16:11

Bronzefry: That's how I read the part.

Coryman wrote:(this may actually be a natural defensive mechanism against predation)

But it also sounds like Ian isn't sure about this either.

It doesn't REALLY make much sense for a fish to emit a suicide substance - I know the Nazis and Communist spies used to have suicide pills, but it doesn't make sense for the survival of the species to kill itself.

--
Mats

Mike_Noren · Post by **Mike_Noren** » 01 Jun 2006, 17:48

MatsP wrote:It doesn't REALLY make much sense for a fish to emit a suicide substance

It is in fact not unheard of that fish release toxins as defence. Cowfish are notorious for doing exactly that, and it is not impossible that Corydoras do too, although on a smaller scale.

Wrt suicide, the response is calibrated to be an effective deterrent in the fishs natural environment, and only leads to suicide in the confines of a transport bag or small tank.

MatsP · Post by **MatsP** » 01 Jun 2006, 18:06

Mike_Noren wrote:Wrt suicide, the response is calibrated to be an effective deterrent in the fishs natural environment, and only leads to suicide in the confines of a transport bag or small tank.

Yes, that was my point: It's no point in fish having a poisonous substance to emit, only to die from it itself. But it may die under circumstances that are different from those that it evolved under. Most fish are not evolved to be transported in plastic bags

--
Mats

Post by **Marc van Arc** » 01 Jun 2006, 18:33

I quite agree with Ian. I've regretfully seen loads of boxes from Manaus, Iquitos etc. containing offwhite, spoilt milk-like water with a whole bunch of dead Corydoras inside. This got better after the exporters put less fish in one bag.
Also his point on oxygen makes sense and may very well be useful to both buyers and sellers, also on LFS-level.

Ian, Doradidae have the same defence mechanism. Their fluid comes from the pectoral gland. Isn't that the same with Corys or does their fluid come from the gills?

martijn · Post by **martijn** » 01 Jun 2006, 18:34

See also this thread

http://www.planetcatfish.com/forum/viewtopic.php?t=4143

Bye Martijn

cartouche · Post by **cartouche** » 01 Jun 2006, 21:55

Yes, I know the German article that the guy mentioned. And I'm also glad that for the first time I saw the poison photographed

I have also heard that the most delicate species to it are sterbai, trilineatus and gossei. O.K., I could stress them a little before catching, but I am a little bit suspicious, if it can help. I would be even afraid that it will actually provoke them to bigger production of this poison. As I said, when the fish were in a bag laid on the surface in my tank, there was no problem with it. So the poison was produced by them not shortly after catching, but as late as during the way, when the bag was in a transport box.

As for oxygen, from time to time I buy imported Corydoras in the wholesale, and they add some oxygen into the bags, although not as highly concentrated as in other fish species. I remember that once I transported 5 adult duplicareus for about 20 hours in an oxygenated bag (only about 22 cm wide), and they were absolutely O.K. Once I also bought big sodalis and they packed them by 6-7 pieces into a bag of the same size with a bit of oxygen. After 10 hours, they showed no signs of discomfort. I also remember that the water was very clean. I think that they may not have fed them before the shipment, and these species may also not produce as much poison as sterbai (that I bought as little fish, by the way).

Anyway, I think that this is a very important topic!

Post by **Coryman** » 02 Jun 2006, 10:42

Marc van Arc

Ian, Doradidae have the same defence mechanism. Their fluid comes from the pectoral gland. Isn't that the same with Corys or does their fluid come from the gills?

The mucus substance was definitely being expelled from the gills and not from the base of the pectoral spine. I and several others made note of this at the time and have since compared it with images of a P. costatus releasing a thicker fluid from the pectoral base.

Personally I thing the act of being caught is in its self is enough to trigger the defence response. If the catching goes easy it may be a little while before the fish's response kicks in and goes into panic/defensive mode, it may not even happen at all. But! I think it is a positive step to get the possible reaction from the fish before it goes into a bag rather than after. C. metae is another I have found to be prone to this reaction. A little controlled manufactured stress has got to be better than a bag of dead fish.

Ian

bronzefry · Post by **bronzefry** » 02 Jun 2006, 14:57

I hopefully will be bagging upwards of 25 Aeneus and Paleatus each(appx.50 total) at a time in about a month and I'm a little nervous about it. I've only bagged a few at a time previously for friends so this is a jump up for me. They'll be between 2-3 months old. Any bag size in particular, do I double bag, how many fish per bag,etc? I'm horrible at netting, so getting them stressed out shouldn't be a problem.

Amanda

cartouche · Post by **cartouche** » 02 Jun 2006, 18:36

Today I took 3x5 big Sterbai to one shop in a neighbouring town. I tried to stress them a little and I waited about 45 minutes before packing. I also added activated coal (about one table spoon per bag, i.e. cca 1,5-1,7 liter). I intentionally prolonged the way to the shop to see, what will happen, because next week I will sell another 10 for a much higher price. I add that the fish haven't been fed since Monday. After 5 hours, the fish were absolutely fine, which pleased me a lot, because during the last way they were almost all dead just after 5 hours.

So, I think that coal may help, but starvation may have been very helpful, too. pH was about 6,6-6,7, so ammonia should not be dangerous and I think that I don't need to buy zeolite.

One man told me that he sent about 50 little pandas in one bag (maybe 1,5-2 liters/0,4-0,5 gallons of water) to his friend and "after several hours" there was no problem with it. But personally I would be more careful. For a 6-hours' way I would pack 20 little Corydoras into 1,5-2 liters, if they belonged to the "self-poisoning species", I would add coal, and I would also lower pH to about 6,5 to prevent ammonia from converting into the poisonous CH3. The fish shouldn't be fed for at least 3 days before shipping. If the way lasted longer, one spoon of zeolite could be very helpful. The water used for shipment shouldn't be taken from a tank. It should be clean aged water with stabilized chemistry.

KevinM · Post by **KevinM** » 02 Jun 2006, 20:13

With other small fish I had before the breeder had used 4" wide x 12" long bags, double bagged.
1 fish in each bag.

edit
I found how someone does boxes.

http://www.petfish.net/articles/How_To/ ... g_fish.php

Kevin

ghost716 · Post by **ghost716** » 03 Jun 2006, 04:51

I have just recently started getting into corys, and in my research I read that about some of them releasing the toxin into the bag they are transported in. My question is when you buy cories from an LFS, say a half hour to an hour from your house, do you think it is safe, or should you ask them to intentionally stress them a little while catching them? I only have 16 corys right now, and I never had a problem transporting them home, but I do worry about that now. Tracy

Post by **Marc van Arc** » 03 Jun 2006, 10:09

ghost716 wrote: My question is when you buy cories from an LFS, say a half hour to an hour from your house, do you think it is safe, or should you ask them to intentionally stress them a little while catching them?

I don't think that'll be necessary, regarding the short time they are in the bag, but you might tell the LFS people you don't want the bag filled with pure oxygen (see Ian's reply above).

ghost716 · Post by **ghost716** » 03 Jun 2006, 15:46

The place I saw this before was somebody had gone to a fish auction and was asking about corys releasing this toxin. I am thinking about going to a fish auction in Chicago, which is about 4 or 5 hours from me. In this case I have two questions. First of all, would you be able to tell by looking at bags of fish which ones have released the toxins into the bags? And second of all, if I were to buy corys from an auction like this, would it help to make a mobile aquarium and have a couple of gallons of water to change it if necessary? Tracy

cartouche · Post by **cartouche** » 03 Jun 2006, 16:12

If you go one hour to your house, then there should be no problems with it, of course, unless you have 30 big corydoras in a small bag. But they would rather die from suffocating than from poisoning.

I think that the problem with the toxin is very insidious, because the fish may seem quite O.K. at first sight, only somewhat apathic and heavily moving, yet suddenly some of them turn with their belly up and are quickly dead. As I already said, the water is usually somewhat milky, and there was a lot of some tatters of dirt in it, but it may have rather had something in common with the fact that I didn't purge the fish properly.

I think that fish offered at auctions are placed in tanks with clean water, not in bags, or aren't they? If you are not sure about the length of your way, then you can't pack the fish densely, and as I stated above, coal may help. And naturally, some sotores of clean water may help, too, if you observe problems during the way.

lotsoffish · Post by **lotsoffish** » 06 Dec 2007, 00:51

I find this thread quite interesting. I killed a bunch of Sterbai"s this Monday. I was packing a lot of orders and got sloppy. I ALWAYS catch all the cories first, put them in a 5 gallon bucket about half full of water and as I am packing orders I keep kicking that bucket as I walk by it. Well this Monday I had a lot to pack so I didn't catch all the cories first. Instead I caught them as I packed boxes and kind of just giggled the containers around for a few seconds, pored that water out and replaced it with fresh water. Needless to say EVERY cory I shipped arrived DOA in fouled, sour, frothy water.

I got to cocky and tried to cut corners and it cost me a lot of money, created embarrassment and worst of all I killed some very very fine fish.

Needless to say I fully believe the theory of cories sloughing off toxins when stressed and I don't think all the carbon or zeolite in the world would have helped those fish once they sloughed off their toxins in my bags.

As a side not, I also usually ship them in Gatorade bottles. No punctures and never any leaks!

apistomaster · Post by **apistomaster** » 06 Dec 2007, 17:37

I'm glad Ian posted those photos.
This is a real phenomenon with Corydoras sterbai; especially young adult or full adult fish.
I was aware of this problem but until recently, I had only shipped hundreds of juveniles and had no problem those.

Then a few months ago I was shipping 25 young adult C, sterbai so I thought I would be fine if I did not feed them for three days and not pack more per bag than what I felt would be safe.

I also reasoned along the lines already mentioned, "What if I "prestressed", then place them in fresh water from their tank for shipping and proceeded to pack them for shipping.
I went to a "fish shipping friendly" UPS station but once I got there my friendly clerk had retired and they no longer were handling UPS accounts. There are few shipping options available where I live.
I still had errands to run so I just went away frustrated and that I couldn't ship that day and finally returned home about five hours later.
When I unpacked the box the water was cloudy and frothy. Some of the Corydoras were dead and the rest were in serious distress. The nature of their symptoms made me immediately think they were suffering from a neurotoxin. Six of those fish died and the rest barely recovered.
I have sold a few thousand Corydoras of other species or juvenile C. sterbai and never encountered this problem. I still don't know exactly how I am going to resolve this and that particular sales has been postponed indefinitely and these are the last of my C. sterbai left to sell.
As it stands now, I am planning to try one per or two per bag and assume all the risks. This toxic shock has nothing to do with ammonia or alimentary wastes.
C. sterbai has one of the most painful stings compared to other Corydoras and it does have the ability to exude a powerful toxin in water when stressed. How or why it has developed this ability is not clear to me but they are rather more colorful than most Corydoras and it is not at all unusual for some strikingly colorful animals to make use of it as a warning to potential predators that to eat them is to suffer.
It doesn't save at the individual level but it can help a species as a whole to develop effective weaponry.
I have been wondering if any of the fish tranquilizers added to the water an hour before catching them and shipping them in the treated water would work?
I have serious doubts that activated carbon or any zeolite is the answer.

Shipping of Corydoras: Coal or zeolite?

Shipping of Corydoras: Coal or zeolite?

Re: Shipping of Corydoras: Coal or zeolite?

Re: Shipping of Corydoras: Coal or zeolite?