Acclimating fish in breather bags

[tolstoy21]

What's the official word on how to do this? Do any of the companies who make them post acclimation instructions? (I've been looking and can not find any yet).

As usual, I read conflicting information one the internet about how this topic, like "don't float, you'll suffocate fish", "don't float the bags are toxic to the existing aquarium environment" to "I float therm all the time no problem".

Like I said, can anyone link me some reputable information, like info from the manufacturers themselves?

EDIT - I don't want to start a fish acclimation flame war here. I'm just hoping someone stumbled across something from Kordon, etc. that addresses this topic.

Edited June 7, 2021 by tolstoy21

[gardenman]

I know nothing official, but since temperature acclimation is important, I half float the breather bags, but prop them up so they're just half in the water and half in the air. It's the best of both worlds option to me.

[tolstoy21]

40 minutes ago, gardenman said:

I know nothing official, but since temperature acclimation is important, I half float the breather bags, but prop them up so they're just half in the water and half in the air. It's the best of both worlds option to me.

Thanks.

Yeah, I've seen a lot of people say they do the same with success on the internet.

I was just wondering if anyone knows for sure, definitively, if the presence of water on the outside of a breather bag (like a closed breather bag submerged in water) can or cannot exchange O2 and CO2 through the bag walls.

I could always bag up a fish and keep the bag underwater for a day and see what happens. But that wouldn't really answer my question. It would only tell me what happened in my scenario. And I could end up with a dead fish! 

I guess i could also just see if Kordon or Long Life respond to customer inquiries. Doesn't cost anything to ask a question!

Edited June 7, 2021 by tolstoy21

[Mara M]

Hi, I too have this question about floating a breather bag. I'm giving some of my fish to my 11yo niece and I would rather not drip acclimate. I bought the breather bags without knowing about possible dangers. Is anyone able to answer this question?

[Guppysnail]

One of the places I order fish from uses breather bags. The instructions that they send with the fish are float to temp open pour fish and water through a net and put fish in the tank. I’ve not had any issues acclimating CPD, panda or Pygmy corydora I’ve received from them this way. Edit I float and add to a qt tank not main tanks. 

Edited December 12, 2021 by Guppysnail

[gardenman]

I'll just repeat what I said back in June. I prop mine up half in and half out of the water. The fish get used to the water temp, and there's no risk of suffocation. No risk, no worry. It's easy-peasy and the safest overall option.

[Gator]

@tolstoy21; I'll let the bag float in my tank for 30 min., then I'll transfer enough water from the bag into a one-pint Mason jar so that it floats upright in my tank. I'll catch the fish to put it in the jar, put two fingers over the mouth of the jar so the fish doesn't swim or jump out as I pour half of that water out so I can refill the jar with water from my tank. I'll let it float for 15 min. and repeat the process a second time, I'll let it float for another 15 min., before repeating the process again. After 15 min. I'll slowly refill the jar and allow the fish to either swim out on its own or I'll slowly pour it into my tank. I've never lost a fish due to lack of acclimation and I've never introduced any diseases into my tank from pouring all of that LFS water into my tanks.

Breathable bags? If a bag will allow oxygen to enter and allow CO2 to escape, it will also allow water to escape which would make for a messy ride home from your LFS. Think about it.

[tolstoy21]

On 12/12/2021 at 9:38 AM, Gator said:

I’m not sure I understand what you’re saying here? Breather bags are designed to allow water to escape?

Since I posted this some time back, I’ve experimented with floating breather bags and didn’t have any issues floating the fish to acclimate them.

My original question was not how to acclimate fish. It was if anyone knew of any published, official stance on acclimation via floating with breather bags from any of the breather bag manufacturers.

Edited December 12, 2021 by tolstoy21

[Gator]

@tolstoy21; I'm sorry, I misunderstood your question, I still have never heard of breather bags before, what are they? My guess is that since I've never heard of breather bags before, I can't help you with any manufacturers' info, maybe your LFS can help.

[Andy's Fish Den]

On 12/12/2021 at 6:22 PM, Gator said:

@tolstoy21; I'm sorry, I misunderstood your question, I still have never heard of breather bags before, what are they? My guess is that since I've never heard of breather bags before, I can't help you with any manufacturers' info, maybe your LFS can help.

Breather bags are made of a special plastic that is water tight, but allows oxygen and gases to flow through thereby allowing gas exchange, so when shipping fish, you just put in the water and fish and then tie the bag right at water level, you don't need to include air, thus taking up less space in a shipping box. 

I have only gotten fish one time shipped that were in breather bags, and I just let sit on top of my tank not in water for half hour or so to acclimate to air temp and then poured the fish and water into a container then over a half hour or so added water to double the amount of water in container. 

[gardenman]

The reason people question breather bags is that when shipped, you're supposed to put something breathable between them. (Wrap them in paper towels/foam/cloth, etc.) "The bags need to breathe." Hence the name "breather bag." Breathing underwater tends to be a tad challenging thus the questions about whether to float the bags or not. That's why I use the half in/half out approach. There's enough water to bag contact to acclimate for temperature, but still enough exposed bag for breathing purposes.

Breather bags are great for shippers as they take up less space with no need for air in two thirds of the bag. You can put a lot more into one shipping box. (Though legally, fish need to be double bagged for shipping and you can't double bag a breather bag.) Just do whatever works for you. I play it safe with the half in/half out approach, but whatever works for you is fine too.

[Phoenixfishroom]

I just tripped over this and I know it is old but I can tell you that I don’t float them and why.

the first time a fish was shipped to me I didn’t know about breather bags yet, floated them, and within a couple minutes all the fish were on their sides. They were all fine again within a couple minutes of me pouring them out of the bags into a bucket.

The second place that I ordered fish rub with aqua imports and they have a big sticker on top of their box that says don’t float them and that is how I learned about breather bags and made an educated guess about what happened the first time. I was curious how everyone else acclimate them so I did a search just now and this came up, I wanted to share for the next person who comes across this page searching that question.

 

[Odd Duck]

@Phoenixfishroom is correct.  NEVER float breather bags!  They MUST have air on the outside of them for the fish to get oxygen.  The plastic bag acts like the water’s surface for exchanging gasses so O2 can get in and CO2 can get out.  Always put entire bag contents into a container (I use a small bucket or gallon pitcher depending on the size/number of fish) big enough to drip acclimate so the tank water brings the bag water close to tank temp.  I drip long enough that I end up with about 4 times the original volume of the bag, then I net the fish out of the mixed water and plop it/them into the tank.

If you float breather bags you will close off those micro pores and the fish suffocate slowly.  That’s why the bags have to be wrapped in porous material like paper between the bags.

[tolstoy21]

@Odd Duck Because I like to test things, I floated some fish in breather bags to see what happened. I just wanted to answer the question through the old empirical evidence. Had them in there for an hour no problems. I'd guess that there was enough 02 in the bag that if the exchange failed they stayed alive.  I did, however, have only one fish per bag, and had just bagged them up. Not sure the same experiment would work had they been in the bag for more than a day or two before I floated them. In general, I don't instruct people to float them, as I'm guessing your mileage may vary and you can just as easily acclimate a fish outside the bag. 

[Odd Duck]

On 3/23/2023 at 6:06 PM, tolstoy21 said:

@Odd Duck Because I like to test things, I floated some fish in breather bags to see what happened. I just wanted to answer the question through the old empirical evidence. Had them in there for an hour no problems. I'd guess that there was enough 02 in the bag that if the exchange failed they stayed alive.  I did, however, have only one fish per bag, and had just bagged them up. Not sure the same experiment would work had they been in the bag for more than a day or two before I floated them. In general, I don't instruct people to float them, as I'm guessing your mileage may vary and you can just as easily acclimate a fish outside the bag. 

I suspect you are right that there was enough O2in your water to not make a difference in that short time.  Did you have any air in your breather bags or did you exclude all (or most of) the air?

[tolstoy21]

On 3/23/2023 at 7:08 PM, Odd Duck said:

 Did you have any air in your breather bags or did you exclude all (or most of) the air?

No air.

[Odd Duck]

Did the bags actually float or fully submerge?

[tolstoy21]

On 3/23/2023 at 7:20 PM, Odd Duck said:

Did the bags actually float or fully submerge?

Floated near the top, but mostly underwater.

I have heard of people floating them and being fine, and other accounts where it led to disaster. So, for me, even though my less-than-scientific test had them survive, it's better to not float them since I've never heard of an account of not floating fish leading to fish death.

Edited March 24, 2023 by tolstoy21

[Odd Duck]

If it wasn’t dangerous to the fish, I might have to run an experiment myself.  But I don’t think I could do that to a fish.  They do have somewhat limited use as far as species.  I know they are fairly impact resistant but I don’t believe they are especially puncture resistant.  I don’t think I’d ever consider sending cories or plecos in them, for instance.  Tetras, danios, rasboras and the like, yes, but nothing spiky or spiny at all.  The plastic feels so thin on them (which is obviously part of how it works).  There’s a couple videos out there of guys that abused them (no fish, obviously) to see if they would hold up to shipping and they did quite well.  There’s videos of shipping and receiving fish, too, of course.  Those are very uneventful.  😝 

[Phoenixfishroom]

I open the bag and pour out half the water then slowly add water to the bag over a half hour to an hour, depending on the fish, until is is at the original height (which I mark with a sharpie before pouring half out). While I am doing that I have the bag in a cup which I float in the tank on a small inner tube meant for floating a drink in the pool.
Once the water is a 50/50 mix of bag and tank water I pour it through a colander and put the fish from the colander into the tank. 
I have never had any negative effects although I am sure they are probably a little indignant about the colander transfer bit. None of them have ever voiced a complaint though.

Edited March 31, 2023 by Phoenixfishroom

[nabokovfan87]

On 6/7/2021 at 5:44 AM, tolstoy21 said:

What's the official word on how to do this? Do any of the companies who make them post acclimation instructions? (I've been looking and can not find any yet).

I would acclimate them the same way as shrimp. To your question I did have something from a bag creator that talked about how to do so. I'll have to see if I can find it again.

When I received them, this is generally what I do. 

Open the box, then try to set them around the tank to acclimate with air temp.

Once that is done, pour the bag into a container and give them a drip acclimation of at least 15-30 minutes.

Edited March 31, 2023 by nabokovfan87

[nabokovfan87]

On 3/23/2023 at 6:49 PM, Odd Duck said:

I don’t think I’d ever consider sending cories or plecos in them, for instance.

I will have to recall the reason why, but I had found some information regarding shipping corydoras and it was pretty critical on what not to do. I found a post on these forums that flip aquatics ships them via breather bags.

I don't recall the specific reason or who it came from, maybe one of the ACO talks?, But yeah....

It might be due to stress and behavior, being stressed out and needing to gulp air at the surface.

.....found it.

Don't ship them with pure oxygen.

 

[Odd Duck]

Another good reason for not shipping cories in breather bags.  But I had a betta shipped to me in a breather bag and he arrived in great shape.  Likely getting enough O2 through the bag he didn’t feel the need to breath air.

[tolstoy21]

On 4/1/2023 at 5:54 PM, Odd Duck said:

I had a betta shipped to me in a breather bag and he arrived in great shape.

I've successfully shipped Mako sharks in breather bags. However, if you put more than two in a bag, you're risking a possible leak.