Fish Shipping Bags- What You Need To Know

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Fish Connoisseur
Dec 31, 2004
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I am getting ready to post on a number of fish sites, even those I will rarely post on. The topic is the hidden danger regarding the bags used to ship fish.
Basically, some of these can and do leech nasty stuff into the bag water.
This is a bit of a long tale but I think it needs to be that way to have it make sense. I am recounting these experiences as much to determine if they are happening to anybody else as well as for getting feedback from folks.

Let me begin with a short amount o background info. I have been keeping fish since Jan 2001. In that time I have had many spawns in my tanks which includes every species of pleco I have kept. From 2003 through Catcon I have likely sold over 500 common tank bristlenose. Since Feb. 2007 I have sold about 400 FI zebra plecos, about 100 L450, about 100 H contrdens and a bunch of other assorted plecos and I have just begun with l236 offspring. I would think over the years I have easily bagged well over 1,000 fish of all kinds but mostly plecos. I had lost only one zebra being bagged in all that time and that one I dinged when catching it and thought it was not injured. Turned out it was and it is the only zebra I ever bagged that did not reach its destination alive until this past 10 months.

I have my own private well with super water. I have digital monitors as well. I am able to and have regularly put water directly from the tap into tanks and used it to bag fish. When I bag fish I pull tanks apart removing the contents to water filled containers. The water is all from my tap and during the netting process I will also take the opportunity to do a good vac. So I refill the tanks when done. I fill my fish use only buckets and larger containers with water and I use the same water to bag the fish and to refill tanks.

With the exception of the summer after 911 when a number of bn shipments arrived DOA, I have lost very few fish in bags whether shipped or transported by individuals.Back then I chalked it up to a potentially "bad" spawn or how the USPO was dealing with boxes to insure they would not explode. Now I am not so sure.

Last year I was a room seller at CatCon. I brought a large number of fish to sell, especially plecos. I ordered a lot of bags in advance of the event. Having used many of them up that weekend, I reordered bags not long after.

When I arrived at the event less than 24 hours after bagging fish, I began to put things into tanks and discovered a number of dead plecos to include some P compta, an L450 and a couple of zebras. Because I had bagged so many fish getting ready, I assumed I might have done something wrong to cause the deaths. For the return trip I repeated the process, this time with dechlored hotel water, the same water the fish spent the convention in. Once again the fish were bagged for under a 24 hours. When I arrived home I had more dead fish. All the rummy nose tetras, and an assortment of plecos to include a few 236 and zebras.

Fast forward to the NEC weekend this past March. At this event I decided to sell out of the vendor room. This time life was easier as it was under a 90 minute drive. To this event I brought plecos, and had delivered from a well know seller a number of Amano shrimp, assorted Nerite snails, rummy nose tetras and Hasbrosus cory. I lost almost nothing on the way to the show, but then the fish were not in their bags very long. However, things which I sold and bagged and were then taken to the room of the buyer started to die over night. In addition the redline barb tank appeared to crash and they died over the 1st night when I was back home. Corys were brought back with a few dead and the rest doing badly. I had a another vendor replace them from his stock and paid for them. Because the time in bags was short in both directions, pleco losses were small, another zebra and a 236.

Fast forward to this weekend and the ACA event. Working with a well known seller and on my own we presented 14 zebra plecos. % ot these were from my f1 adult tank, the other from two different growout tanks. All the fish were bagged individually. Also there was one bag with 2 L236 at 1.5 inch and a bag 2 with 3 L450s of a similar size. All were well bagged in clean new water with nothing added but a small piece of Poly-Filter fiber. The fish were bagged Thursday morning between 9:30 am and 1:30 pm, taken at about 2:30 and at the event by about 5. The 5 adult zebras were collected that evening and unbagged into a tank in the buyer's room. Friday morning at about 10:30 I got a call from the person handling my fish, the buyer for the other 9 zebras had arrived and when the styro was opened, all of the 4 biggest (1.75+ inch) zebras were dead. The 5 smaller ones were still alive as were the 236 and 450s. However, it was agreed the fish should immediately be rebagged. The bags were from another supplier and the water was now dechlored hotel water. I told the buyer to take the five fish and if they lived in his tanks for at least a week we would settle up. On the way home one of the five fish died. he reported the other 4 went to cover as soon as they went into his tank.

That evening I heard from my associate at the hotel. One of the 236 in the new bags had died, Only the L450s were still intact. I was also informed the 4/5 F1 adult zebra plecos in the buyers' tank had died overnight. I refunded their money.

Now here are all of the sort of details one might want to know about:
1. I have used my tap water untreated since day one in the hobby and never had issues in tanks or bags until recently.
2. I store bags as they came packaged, I further put them into plastic bags like one gets for their groceries and then into an open box in the storage area where I have two inwall tanks running.
3. I normally ship with a small amount of Amquel in the bag water. This last time i chose not to use any Amquel instead adding a small piece of Poly-Filter.
4. For both of the above events I brought cycled filters for all the display/sales tanks. I maintain a small bio-farm to jeep additional filters cycled and ready to use.
5. I will dump my bag water into the show tanks when the trip is short.
6. For the NEC event I brought my own tank water using my normal RO/di storage containers.
7. I use heat packs as needed and tend not to ship during the Thanksgiving (USA) and New year period. I will never ship when its extremely hot.
8. Since I got two orders of bags on top of the one's I already had, and because I tend to mix them easily, I have no way to associate any bag with any specific purchase.
9. On a fair price basis for the sale amount for my F1s and the other fish I purchased for resale, I have now lost over $4,000 worth of fish.

All of the deaths I am discussing here clearly happened in relation to fish being bagged in my bags. It appears that the longer the fish are in the bags, the more that die in them and the more that may have still survive have died after being unbagged or rebagged in different bags and water. So I have two issues that I would like to have some input on from folks with a decent amount of experience with shipped fish.

First, does anybody see any other reasonable explanation besides contamination from the bags?

Second, this problem seems to happen for me mostly, but not exclusively with sucker mouth cats. Since these fish tend to suck onto the bag during transport, is it possible that may be an important factor? Might the fish be causing the release of chemicals or some form of breakdown in the bag integrity which greatly exacerbates the potential for chemical issues to occur by sucking on and/or rasping the bags?

I have brainstormed this problem with several people and we all keep coming back to the same thing, its the bags. The upshot is I am throwing out all of my current stock of bags and replacing them from a different supplier. I have related most of this information to the vendor from whom I bought the bags. I know he is on a road trip, so I do not expect an answer from him until later next week. I believe the vendor is not directly responsible for the problems if it is indeed the bags.

Edit: There is a July 9 article on the subject of killer fish bags which only deals with saltwater fish. It reported in Amazonas/Reef to Rainforest here

I have reached out to the corresponding author to aks if they have any data on fw fish in bags or plans to investigate. I mentioned the idea that the sucker mouth fish may cause or exacerbate the release of chemicals. If and when I hear back I will report this.
It contains my personal experiences, links to recent scientific research on this subject and an article/interview with the one of the authors of the paper. Here are a few of the details:
1. The organization doing the research is non-profit. The research was undertaken because one of the researchers is friends with somebody in the fish business who has suffered some serious losses over the years.
2. I contacted the author over the weekend and got a nice reply back.
3. I talked by phone with SeaChem today regarding their new bag for retail stores. I doesn't contain the offending chemical.
4. I contacted another vendor who specializes in fish room supplies and chatted with them. I ordered bags from them to replace those I had to throw out. I chose them on the advice of somebody who had a similar experience with the vendor I have always used and who switched suppliers and has not had further issues.
5. The scariest part of this all is that often it takes a fish about a week after being in "contaminated" bag water before it dies. Therefore, most people will never suspect the real cause of fish losses shortly after they go into a tank. However, losses during shipping are quite common as well.
6. It appears as if the problem way be exacerbated when shipping plecos.
If you read the thread and are interested, i would like to hear how you think we can spread the word and then apply pressure on the bag makers vie the people from whom we buy our bags to push them to make safer bags.
And and all comments, thoughts and suggestions are welcome in this thread.
Also for those interested in this topic to you can read my thread on Planet Catfish - Shipping Bags & Fish Dying
If you would like to read the original research, you can find the full paper here http://www.haereticu...osphere2015.pdf
If you want to know about the Haereticus Environmental Laboratory you can visit their site here
Hmmm very interesting, I work in a pet store now, and im definitely going to have to look into this and see if we can minimize losses from shipping, im not sure what bags our wholesalers use. Its Segrest Farms and Raleys, ill read up on your link now.
I can help you re Segrest. I was told this by a friend who is in the fish importing/breeding side of the business. I was told that Segrest are aware of the problem and even tried to address it themselves. Unfortunately, they used the wrong approach. They tried to set up their own manufacturing facility and the costs involved were high and they were unable to make it break even let alone be profitable. So they gave up on that side of it. But I would bet they have a deal with a manufacturer who agrees not to use nonylphenol in their manufacturing process or to keep the levels extremely low. There is a "safe level" but it is very low.
What needs to happen is for this information to penetrate deeply on the level of hobbyists. We need to make a stink about this with those from whom we get fish. This pressure will cause the vendors to bring pressure to bear on the bag makers. There will be a cost, the price of bags might double. or it might not.
SeaChem is selling their non-nonylphenol bags with pictoral directions for acclimating on them to retailers etc. I can buy 100 of the 4 x 16 inch 2.5 mil bags for about 10 cents each in 100 bag lots. I can buy 2 mil bags from my supplier for 4.5 cents each at 4 x 18 inch or 3 mil thick for 5 cents each. So if I put one fish worth $5 into a bag and have it possibly die for about a nickel or I can spend 10 cents for the bag and likely have the fish live. I do not need an economics degree to figure this one out.
The problem is one of corporate motivation. If there is not pressure put on the bag sellers and makers, then we the fish keeper will suffer. What makes this worse is that in many cases the fish may not die in transit. It may not die for a number of days after it goes into your tank. Many fish sellers wont guarantee fish much beyond their arriving alive let alone days later. Hobbyists bring home fish which seem fine, put them in their tank and when they die 5 or 6 days later the assumption is that the fish keeper has done something wrong more often than not.
This may seem a silly question but most fishkeepers do not use plastic bags, generally they will only come across bags when buying from LFS and even then, these fish are only in the bags for a short period of time which is usually for the keeper to get from LFS to their home.
For folks that ship stocking for a living and for those who have have prized, specially bred or expensive stocking, this is a different matter entirely.
Is the amount of time that fish stocking spends in the bags pertinent to the issue at hand?
Also this seems to affect, as you say, plecos or sucker mouth species which rasp at the bags which may quicken the leaching of nonylphenol which seems to be the centre of this.
So, if you're transporting, say for example, tetras, then this may not be an issue since they wont rasp or really do anything with the plastic of the bags?
And finally, would adding anything into the bags help to prevent nonylphenol from occuring into the bag water?
Prime or known brands dechlorinator for example (of course being specially careful not to overdose this)
I'm wondering if adding a bit of wood to the bag would help.  I know when shrimp are shipped, they are always sent with a bit of plant to hang on to during the shipping process... I wonder if shipping some sort of 'anchor' along with the fish would help - or would their be too much risk of the fish being crushed during the shipping process?
The wood would also be expensive to put a piece into every bag for the most part, and in any case it was just TTA's theory that rasping on the bag may quicken the release of the chemicals. A normal bag with any fish that floats in the water column is still at risk to nonylphenol exposure within the bag, on a long drive home it could be a bad trip for the fish.
Also some hobbyist may use large plastic bags when moving to a new house, which would mean a long term exposure to leaks in the bag, I can see many problems with this if its true.
Ive seen those seachem bags before, theyre very cool and have a privacy film for the fish to feel safe as well which i love, as well as the acclimating tips on the bags.
Not to be 'that guy', but the rasping on the side is an hypothesis, not a theory.  (Sorry, just a pet peeve of mine.)
Sorry to hear about your losses TTA.  It must have been heartbreaking to see hand-raised fish dying for no apparent reason.  I hope you have better results with the new bags.
It is a hard situation to deal with overall. What I am not looking at is the potential effects of these bags where they do not kill any fish. At non-lethal levels that can even be fairly low, nonylphenols cause reproductive disruptions in fish. This means one may be buying fish that might not be able to reproduce. While this may not be a big deal for the average fish keeper, it would be for those who breed fish.
The next problem is there is not a lot one can add to bags to deal with this problem. One suggestion from Dr. Downs was to use pellets of medical grade carbon which have been activated.
And do not be fooled into thinking that because you buy a fish at the store and it comes home fats and is only bagged for a couple of hours at most. Those fish you are bringing home in that bag did not walk to the store, they arrived in bags. They will have come from a wholesaler or an importer. And this means they could have been in bags many more hours or even a day or two at that stage. Then lets consider how those fish got to the wholesaler or importer. Again a day or so bagged if they are shipped airport to airport without delay. International live fish shipments do get bumped now and then.
So in the end that fish from the store has spend plenty of time in various bags to get to the store. Unless the fish actually die in transit or during that week or so window after, all we know is the fish are alive, We have no clue if they have been harmed in other ways which may prevent them spawning or shorten their lives. The research looked at mortality not other potential issues.
Since the only way to know a bag is most likely 100% fish safe is to manufacturer them to stringent specifications which eliminate all the likely ingredients that might cause the problem. For now this would be nonylphenol. But SeaChem has clearly jumped all over this but in a minimal way- its one size bag and the directions on it for acclimating fish would never be used by those who ship fish in bags where they are in transit for one or two days. Fw fish dealers etc are mostly plop and droppers- open the bags and get the fish out ASAP and into the holding tank. For them trying to acclimate fish mostly kills a lot of them.
I cannot use the SeaChem bags due to the one size. It is smaller than the bags I normally use when shipping. I wish this was not the case. One thing I do know is that the breather bags do not have this problem. Unfortunately, these bags cannot be used for a lot of species, one of which is plecos.
My new bags in transit will be tested here with live fish before I will risk using them for fish I would be selling.
After reading the linked article and information on Wikipedia about nonylphenol, The best preventative measure is to wash the bags before using them.  Apparently nonylphenol is water soluble and often used as surface coating lubricant on the plastic.  So washing should be effective in removing it if it is present.  Unfortunately no one washes plastic bags before use and there is no way to know if it was washed by the manufacture.
As a side note I recently purchase Otocinclus online and did loose one within days of being added to my tank. I don't know if it was the plastic or something else.
Rinsing only deals with the slip agent. A certain amount of this is used externally so one can separate the bags from each other and, I believe, not so much inside the bag. I saw nothing on the concentrations that might be involved with such use this. Rinsing has no effect on preventing leaching of nonylphenols from the bag in contact with water. Not all bags made with nonylphenols use it as a slip agent as well. There are other products that will do it that do not contain phenols.
Bear in mind that fish are bagged and rebagged a few times before they come home from a store. The time they spend in bags ie more like one to two days during such trips. Who can say what the cumulative effect could, be. That last hour or two trip home from a store is not the main issue. And for the trade, the small time operators and for hobby breeders like me me, it is an issue since are fish are bagged for a lot longer.
"Rinsing has no effect on preventing leaching of nonylphenols from the bag in contact with water."  
In the original article they found nonylphenols (NP) on Teflon bags.  Teflon is made by exposing a gas to catalysis.  NP is not used to make Teflon and Teflon does not leach anything.  The researchers cleaned the Teflon per EPA specs and found no  NP after the clean.  Polyethylene is also made by exposing ethylene gas to catalysis.  Unfortunately feflon and raw polyethylene are translucent plastics and are not often used when shipping fish.  The aquarium shipping industry prefers clear plastic bags. There are a few plastics out there that don't have NP in them.  from what I have read Europe has basically banned NP and the EPA is trying to get it phased out.  In Asia and South america there are no restrictions on NP.  
They tested food grade, clear plastic bags in the research, they are the ones labelled PE1 and PE 2
We exposed marine orchid dottybacks (Pseudochromis fridmani) for 48 h to either glass, Teflon, or two bags labeled as FDA food-grade polyethylene (PE1 and PE2) from different manufacturers. The PE2 bags leached high levels of NP into the contact water, which were taken up by the fish, and decreased short and long-term survival. Concentrations of NP that leached from the bags were consistent with 96 h LC50 values determined in this study, indicating NP is the likely toxic agent. Despite being similarly labeled, the NP concentrations that leached from the bags and the resultant toxicity to the fish varied dramatically between manufacturers.
Both bags PE bags were labelled the same way but one was highly toxic. The gist of the study is that bags which are labelled as food grade still may leach nonylphenol even though they are supposedlt safe..
Just a quick update-
Over the weekend my new bags arrived. Yesterday late afternoon I bagged up a 1.375 inch L236 in a 4x15 inch 3 mil and then another 3 slightly bigger in a 6x22  inch 3 mil, and parked them in a styro and set it atop a breeder tank in-wall which should keep the temp in the high 79s F. I will check on them this evening which would represent about 1 day in the bags.
I don't know of this was just my imagination or wishful thinking, but the new bags seemed to me to be clearer than the older bags. It may be that over time that bags naturally become more opaque. I do not know this to be the case.
I will report the results of the test when I am done.
Sounds plausible about bags becoming more opaque over time, though is that anything to do with the issues at hand. Not sure.
Do keep us updated.

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