How to bag and ship live fish

How to bag and ship live fish

You can ship live fish with USPS if the fish can fit inside USPS’ box size regulations, and if you use enough packing material to fully absorb any leaks. Shipping live fish with the US Postal Service is fairly simple, and we’ve listed out the basics for you below.

Properly Packaging Your Live Fish for Shipment

Here’s how to properly package your fish shipment, with some regulations thrown in from USPS’ website:

  • Fill a plastic airtight bag halfway with water, place your fish inside, and tightly tie off the top
  • Place the bag containing the fish and water inside waterproof inner packaging, such as an insulated styrofoam box
  • Cushion your plastic bag with enough absorbent material lining the foam packaging to take up all liquid in case of leakage (think towels, rags, etc)
  • Place your inner waterproof packaging inside a new corrugated cardboard box, then seal it

If you’re looking for some foam packaging, check out this insulated foam shipping kit from ULINE.

Which USPS Service to Use (and When)

You’ll want to use either Priority Mail or Priority Mail Express for your live fish shipment. Speed is a crucial factor when shipping live fish, so the faster the service, the better. Priority Mail Express is USPS’ fastest shipping service, with overnight delivery between most urban centers, and 2-day delivery to and from rural areas. If you don’t want to pony up the extra cash for Priority Mail Express, then regular Priority Mail should still get the job done between 1-3 business days.

Also, we suggest shipping as close to the start of the week as possible. Generally speaking, the earlier in the week, the better. Sometimes the weekend throws delivery schedules off a bit, and you don’t want your fish to stay in transit any longer than they need to.

Pro Tip: Shipping live fish is entirely different from shipping fresh (killed) fish and other seafood. However, you can still follow this same process for shipping other live sea creatures such as shrimp and prawns.

Do You Need Insurance?

Keep in mind that all Priority Mail Services come with $50 of insurance at the Post Office, and $100 when you buy labels with shipping software. If your fish are valued more than that, it never hurts to protect your package with extra shipping insurance.

Save Money on Your Fish Shipment with Shipping Software

As always, you’ll save the most money on any Priority Mail or Priority Mail Express packages when you use shipping software to buy discounted postage online. The best shipping software options allow you to access special USPS discounts such as Commercial Pricing. USPS Commercial Pricing represents the highest level of savings that USPS typically only offers to huge commercial shippers sending out more than 50,000 parcels a year. Plus, shipping software lets you print your shipping labels at home and skip the lines at the Post Office!

Today I want to share my favorite method for shipping fish safely!

I have never lost a fish using the following method.

You can use this information if you are selling fish to a customer OR if you are needing to prepare your fish for moving to a new house.

Oh, or maybe just sending fish to a friend in the mail.


  1. Fast the fish for 24 hours prior to shipping. This will help prevent fouling the water.
  2. Fill a plastic shipping bag with about 1/3 water treated with Seachem Prime. The water should be just enough to cover the dorsal fin of the fish when the bag is tipped on its side.
  3. Add the fish to the water.
  4. Quickly grab the bag near the top to trap as much air as possible inside (but leave enough room for twisting). Alternatively (and even better), use pure oxygen to fill the bag.
  5. Twist the opening of the bag as much as possible so the twisted part folds over a couple of times and secure with a rubber band. The twisting is what creates the seal. The rubber band helps to hold it in place. I like to use 2 rubber bands at least.
  6. Take another plastic shipping bag and slide it over the top of the first one (so the top of the inside bag is at the bottom of the outside bag). This will make a nice smooth bottom and prevent fish from getting trapped in the corners by compressing them to the sides.
  7. Twist that bag also and rubber band securely.
  8. Use packing tape to fold and secure the bottom corners of the bag “tails” underneath (optional but looks much more professional).
  9. Place the bag(s) in a Styrofoam insulated box. Add any care instructions sheet.
  10. Fill the empty space around each bag with peanuts and/or air bags. The fish bags should remain very secure if shaken. The journey is likely to be bumpy!

    Mail the fish overnight or Priority mail 2-3 day, depending on the weather in your area and the destination area. How many fish you add per bag depends on the size of the fish. For goldfish, 1 goldfish per bag is a good rule of thumb, but a large bag may accommodate 2 small goldfish. Using pure oxygen to fill the bag can increase the number of fish per bag, as oxygen is the greatest limiting factor when shipping fish. The volume of water is not as important because if the fish runs out of air, it can cause brain damage and even death. Properly packaged fish are known to last 7-10 days in the bag, though it is best to minimize the time in transit to minimize stress by shipping quickly. FedEx priority 1 day shipping and USPS 1 day shipping will come to your door and pick up your shipment. They always prioritize live animals on their deliveries by dropping them off first. Yes, one-day shipping is very expensive but it goes with the territory. A Styrofoam insulated box is essential for almost every situation. It protects the bags from impact and regulates the temperature. Depending on the weather, use a heat or cool pack as required. Keep in mind some of these only last for 24 hours.

Choosing the Right Shipping Bags

How to bag and ship live fish

Image Credit: Alex Violet, Shutterstock

I use this sturdy plastic kind on eBay, always double bagged as described in the instructions above.

There are bigger and smaller sizes available, depending on what kind of fish/shrimp/plants/invertebrate you are shipping:

Some people use breather bags, but I have never had success with those.

They are extremely fragile.

That is because the walls are thin to allow the oxygen through.

I feel it is like trying to ship a bubble ready to pop at the slightest jostle, and I and other experienced fish breeders have lost fish shipping with them.

I think it’s much safer to have the oxygen at the top in a stronger bag.

You can also use square bottom bags if you want to avoid the tape method. This might save you time if you need to ship a lot of fish.

Choosing the Right Shipping Box

You can use the kind that has a built-in lid and wrap it in brown paper or put it in a slightly larger box.

But you can also line any box with sheets of custom cut Styrofoam insulation.

Cutting Styrofoam yourself can be a huge pain and a giant mess (speaking from experience here)…

… So some people sell kits of pre-cut Styrofoam for specific box sizes available from the post office.

These can make things much easier.

You can use what works best for you!

Your Thoughts

I hope someone finds this post helpful!

Now I want to hear from you.

Have you ever shipped fish before?

Want to share your own tips?

Share your comment below!

Featured image credit: hairyeggg, Wikimedia CC 2.0

This document contains:

Shipping Live Animals – Domestic and International

UPS provides service on a limited basis for packages containing some types of live animals. The term “animal” as used herein refers to anything living, except plants. While the list of “Accepted Live Animals” provided herein is an exhaustive list of animals that can be offered for transportation in accordance with the conditions listed, the list of “Prohibited Live Animals” is only a partial list of animals provided to clarify specific species that are not accepted for transportation and may not be shipped via UPS. Any animal not specifically listed on the “Accepted Live Animals” list is prohibited by UPS and will not be accepted for transportation. All international live animal shipments require an International Special Commodities contract. Contact your UPS Account Executive for information about shipping International Special Commodities via UPS.

Packages containing live animals must be prepared in accordance with the requirements as specifically stated herein. Packages containing live animals must provide for the basic humane care and safety of the animal during transportation. Any package containing a live animal shall be considered a perishable commodity and will be accepted for transportation solely at the shipper´s risk for any damage or loss arising from the perishable nature of the item. UPS shall not be liable for any special, incidental, or consequential damages.

All shipments of live animals must be clearly marked on opposing sides of the carton in bold block lettering a minimum of one inch in height stating: LIVE ANIMALS. The term animal may be replaced with the name of the specific live animal contained in the package.

In the event a package containing a prohibited item is found en route or in the UPS system, that package will be stopped at the location or UPS facility of the discovery. UPS reserves the right to dispose of the package.

*Hawaii – All live animal shipments to Hawaii are subject to inspection by the State of Hawaii Department of Agriculture upon arrival. Service delays may occur due to this inspection. Live animals may only be shipped to the island of Oahu. Importing Turtles/Tortoises into the State of Hawaii requires a permit prior to importation. Please review the information on the following web page for specific requirements ( Shipments of live animals to Hawaii may be more restrictive than the limitations listed herein. (Please see the Animal Guidelines page on the State of Hawaii web site for more information.)

Endangered or Threatened Species

In addition to the Prohibited Live Animals list provided here, any live animal or plant that is an Endangered Species is prohibited by UPS and will not be accepted for transportation. Shippers must refer to the most current publicized list posted on the U.S. Fish and Wildlife Service Web site.

Service Type

Live animals will only be accepted for transportation when shipped by any UPS service that guarantees delivery the next day. Shipments must not be offered to UPS on Fridays or before a holiday in the origin or destination country.


Design and Construction of the Primary Container: All live animals offered for transportation must be in a new box. Corrugated boxes must be constructed of a minimum of 275 # bursting strength corrugated or 44 edge crush test. It is recommended that any package containing animals requiring moisture during transportation be constructed of water-resistant material such as wax coated, wax impregnated, or plastic corrugated. Minimal ventilation holes should be provided as necessary.

Internal Packaging and Other Considerations: Internal packaging materials must be used based on the characteristics of the animal, taking into consideration the necessary humane care for the animal while in transportation. Lizards and geckos should be individually contained in bags constructed of breathable material, such as burlap. Insects should be contained in individual primary containers such as plastic jars with ventilation. Fish must be double bagged in strong plastic bags with a minimum thickness of 4 mils. Each primary bag should be approximately one third full of water with the remainder filled with oxygen.

Package Testing: Any packaging used or developed to transport animals should be submitted to an International Safe Transit Association (ISTA) certified package testing laboratory for pre-shipment testing in accordance with ISTA Procedure 3A before being offered for transportation.

Additional Considerations: Additional components such as food, moisture, and temperature controls should be added as necessary to provide a safe environment during transportation. Additional dunnage should be added to prevent movement of the primary containers or receptacles within the outer box.

Requirements for the Acceptance of Live Bees

As of 1/1/2021, UPS will no longer accept, for transportation via Air services, shipments of Package Bees, but will continue to accept via Ground service where the time-in-transit of the shipment from origin to destination ZIP codes is no greater than one day. Shipments of Queen Bees, with their attendants, will continue to be accepted for Air and Ground services where the time in transit between origin and destination ZIP codes is no greater than one day. You can check times in transit at

Packaging Requirements for Bees:

Bees that are shipped within the traditional wooden crate with wire mesh must be enclosed in a corrugated sleeve. This sleeve must include a border of a minimum of 2 inches past each edge of the container (See diagram below). This is required to prevent safety hazards from protruding wires from the mesh. UPS will also accept “Bee Bus” packaging. Any package other than described herein must be tested in accordance with the Package Testing standards described above.

Note: Corrugated sleeve must overlap the edge by at least 2″.

Live Bee Food Supply Requirements:

Welcome back to the Jack Wattley Discus hatchery. This is Gabe Posada, and today we are going to be talking about how we bag the discus for shipping, what it takes to make sure they stay alive during travel, and the precautions necessary to ship fish. We are responsible for the fish until they make it into your tank, so we take extra care, as you will see in this article, to make sure every possible complication that could lead to a fish death during shipping is accounted for and covered before they go out.

The Bagging Process

First of all, once an order comes in we select the fish and extract it from the tank with a net, we then quickly place the fish into the proper bag. Generally, there are three different sizes of fish – small, medium and large, and each size gets its own corresponding size of bag. Every bag has a special liner inside of it to protect the bag from being ripped or punctured by one of the fish’s fins. This is the primary preventative measure we use to help minimize the chances of puncture from inside the bag.

Our next step in the process is to fill the bag with pure oxygen. Once the bag is full we staple it shut in a special way that creates a leak-proof hermetic seal. In the old days, we used to seal the bags with a rubber band, however; we have since found that stapling is more efficient and reliable. After the initial bag is stapled, we then wrap it in two more bags and use a stapling machine that does both at the same time. This ensures that punctures from the outside of the bag are highly unlikely and offer extra layers of protection.

The Boxing Process

Once the bag is properly sealed and stapled, we then put it into a styrofoam and cardboard box. If it is a larger order we place many bags into a much larger box, also made from styrofoam and cardboard. Since these are live tropical fish, we go above and beyond when shipping them to colder climates or during naturally colder times of the year. During the winter months, we place 40-hour heat packs into the box to make sure that the fish make it to their destination safely, and the cold weather that they may encounter does not affect them.

What If My Fish Arrives Dead?

Although we have years of experience in shipping tropical fish and take every possible precaution, anything can happen and sometimes they don’t make it alive. We are shipping live tropical fish after all! If this happens, however, don’t worry, all you have to do is get in touch with us, send us a picture and we will be more than happy to either replace your fish or give you a full refund.

Want to Learn More?

Well, that is it! Our bagging process for shipping the tropical discus fish is really pretty simple. We hope this gives you a better idea of how we make sure all of our fish get safely to your home, directly from our hatchery. As always, we truly hope you guys enjoyed this and please keep the questions and comments coming.

If you want to learn more about what we do here at Jack Wattley Discus, you can find tons of great content from us on Facebook, Instagram or YouTube.

How to bag and ship live fish

If you can’t go to the fish, perhaps the fish can come to you. Here are the essentials of shipping and receiving fish through the mail.

If you’re new to the aquarium hobby, you’ve probably said this to yourself: “I really want this fish… but I can’t find it at any stores in my area.” It may surprise you to know that you can order fish online and have them delivered right to your door. Shipping does have its pros and cons, but if done correctly, in most cases, the fish will arrive safe and sound. There are a few tricks of the trade to help get your fish to you, or for you to get fish to someone else, safely.

Picking a Shipping Choice

There are several options when it comes to sending or receiving fish. Typically, when buying fish, the seller will offer a variety of USPS services. Priority mail means that the package will arrive to you in 2-3 days. Most sellers do not guarantee live arrival with this option, although some do. The biggest benefit to this option is that the price is lower, as shipping can get pricey. The cons are that the fish are en route much longer and exposed to a lot more dangers. It still can be a safe shipping option, however, if the seller is responsible with packaging and knowledgeable about the rest of the items on this list.

Another option is overnight or expedited shipping, through USPS. Just as it sounds, the package will arrive to you the following day. This option is more expensive, but offers peace of mind that the fish will not be exposed to more dangers than necessary.

FedEx and UPS are also options to ship fish. They are more costly, but offer the same types of options as USPS, and many hobbyists will say that one of these are the safer route to go. It’s up to the buyer and the seller to take all variables into account.


Whether you are shipping or receiving, it is important to pay close attention to the weather both where you live, and where the package is going. Look for temperatures over 50 F (at the lowest) in both locations, to be safe. Some sellers will still ship if temperatures are lower than this, however it may void any live arrival guarantee that is in place. While those of us on the East coast may often focus on cold temperatures, it is equally important to look at the warm temps. When buying during peak weather times, it is almost a necessity to request a heating or cooling pack based on the weather. They are inexpensive, and add another level of caution.

Sellers should always insulate their boxes. Some choose to line the inside of the box with insulation like you would use in your home, while others will use foam coolers inside of the box. Whatever the method, insulation will help keep the heat or the cold inside or outside of the box (depending on weather), and keep the fish at a consistent temperature.


When it comes to bagging for shipping, double bagging is a must. Fish should be placed in\ one bag, rubber banded shut, and then placed into another bag. This will protect the box should one bag burst or leak.

Don’t forget the air. Some sellers will use specifically designed bags that allow for oxygen to permeate the bag, and for co2 to leave. Others will use oxygen tanks to fill the bags with clean air, and others yet will just use room air. Whatever the method, make sure that the fish have air to use throughout their journey.

Fish should always be packaged with fresh, clean water. Adding a few springs of plants in the bag will help eat up excessive ammonia and nitrites while they travel, and using a good water conditioner is invaluable.


When you’re ready to package up the fish, use crumpled newspaper, packing peanuts, shredded paper, or any other soft material between multiple bags, and around the bags, so that they do not fall over and move around the box. This will help eliminate risks of the bags becoming damaged, and will make a smoother ride for the fish.

Stay Informed

Whatever shipping method is chose will have a tracking number so that you can follow along the journey. Keep this number, and pay close attention to it. Checking it once or twice a day to make sure they are on the right path. Occasionally, tracking numbers won’t update, and it’s seldom a reason to panic. Red flags to watch for are if your package has stayed in one place for what seems like a long time, your package is somewhere completely out of the way in reference to where it is coming from or going to (for example, you live in Ohio and your package went to California after being shipped from Florida). If your package does not arrive within the specified time frame do not waste time, call the shipping company and try and get as much information as possible. In some cases, the package will have insurance on it for the rare instance that it is lost, stolen, or damaged. Check with your specific shipping company for details on what is covered.


When live animals are transported, it is almost inevitable that you may ship or receive a fish that doesn’t make the journey. Sometimes, even if everything else was done right, they still do not live. The first thing that you should do is take a photograph for the seller, in an unopened bag, clearly showing that the fish was DOA. The more pictures you can take and the clearer they are, the better. These should be sent to the seller as soon as you possibly can, to show that the fish was deceased upon arrival, and not after the fact. If your seller had a live arrival guarantee they will then make arrangements to either refund the cost of the fish, or to send a replacement. It is important to note that they are only responsible for the fish, not for the total shipping cost.

With all of this being said, it can be overwhelming. In most cases, if both the buyer and seller are informed, little to no problems will arise. Communication is key to making sure that everyone is happy, on both ends of the fish shipping system.

How to bag and ship live fishSummer Davis is the mom of three kids, four dogs, and several tanks of fish. She boasts a passion for all animals, whether they are in the water or on land. This fish aficionado has kept many different species in her time, but holds a special place in her heart for wild and domestic bettas. When she’s not talking about fish, Summer “spins” her extra time as the director of a baton twirling organization.

  • Mar 2, 2010
  • #1
  • Alpha Aquaculture

    Designer Clownfish Hatchery

    So you are thinking about shipping.

    maybe I can help

    I always try and get people to ship FedEx to a FedEx Office address. They might not accept any packages from other carriers. FedEx is not the only carrier you can use. UPS is a good carrier but many have had issues using USPS. Shipping to a FedEx Office location is the safest way to recieve live packages as I have had many issues with the delivery guys on my route. They have left packages out in the cold as well as other issues. When having packages delivered to your home, they generally are tossed around more on the truck. The truck might also get cold or hot reducing the survivability of your coral.

    FedEx Priority Overnite is an overnite delivery arriving before 10:30am. Its usually quite pricey, like $60-70. Most people and companies take losses on shipping. There are some good threads you can search for to minimize this shipping expense, like setting up an account with fedex etc. Shipping that arrives later than overnite 10:30am is more of a risk for you because the coral has a lower survivability. Its a shame to loose such a beauty piece to save on shipping and if it dies its usually understood that the seller will be responsible and have to ship another frag for free or refund the money.

    Longer cheaper shipping is especially risky in the winter and summer. In the winter you might need a heat pack. Use the 40+ hour ones nothing less, just in case it gets delayed. Also, this is important. make sure the heat pack is warm before you close the box. I have had a few die in the last few months due to shippers not checking. In the summer it might be necessary to add a cool pack. There are many ways to accomplish this some as simple as a triple bagged bag of frozen water. Other cool packs are available. Optimally a shipper checks the weather in the destination city and then makes an educated decision.

    Make sure you bag up properly (3 or 4 layers) so the bags don’t leak. Some use metal clasps, heat seals, rubber bands, or simply tying the bags tight. Ime most leaks occur in rubber banded bags. Use plenty of packing to make sure the bagged coral does not toss around or even move at all. Put a few layers of newspaper between the bag and the heat pack to make sure it doesn’t get too hot or cold. Use an insulated styrofoam shipping box.

    This is important, do not tell fedex that its a live package or coral, lie to them or they will not accept it. Try and use a box that says perishable on the side and this side up arrows.

    Keep in good communication with whoever is recieving the coral. Don’t ship without an ok on the address, time, date, and carrier from the reciever. Include the recievers phone number with the address on the package. Ask for constructive criticism about your shipping methods after your package has been recieved. Start off with a few cheap corals as a gift for a friend Give your frags plenty of time to heal after fragging. Be cautious when shipping stressed corals. Sometimes stuff dies in shipping. It happens! All that you can do is try and make it right with the reciever and learn from it!

    I hope I covered everything. If not feel free to add input or corrections/constructive criticisms.

    The Original Oxygen Transfer Fish Transport Bag

    How to bag and ship live fish

    Don’t be fooled by other bags claiming to do what Kordon’s Breathing Bags do – there are no “Second Generation Breathing Bags” that are produced from the same or improved material or that can claim the same Oxygen Transfer Rate as genuine Kordon Breathing Bags.


    Breathing Bags are a completely new approach to the shipping of live fishes, as well as aquatic invertebrates and aquatic plants, in plastic bags. The special plastic film used in the Breathing Bags generates the constant transfer of carbon dioxide out of the water in the bag through the walls of the bag, and the absorption of oxygen from the atmosphere through the bag walls into the water in the bag. This provides a constant source of fresh oxygen that fish and other aquatic specimens use to breathe.

    Kordon ® Breathing Bagsв„ў represent a new approach to the problems of shipping live fishes and other aquatic animals and aquatic plants, including over long distances or for extended time periods. The product development staff at Kordon, teamed with plastics chemical engineers, have taken a technology first developed in space/military research and refined it to produce the bags being offered today.


    The Breathing Bags are constructed of a special film that has a micro-porosity that allows the transfer of simple and complex gas molecules through the plastic wall of the bag. Carbon dioxide and oxygen in particular, as well as other gases – are constantly passing through the plastic bag via the micro-porosity. In other words – the plastic has gaps so small that water molecules cannot pass through – yet gas molecules can move freely. This provides a true “breathing” bag in place of a non-porous “barrier” bag as is used in traditional plastic polyethylene bags. As long as there is a breathable atmosphere outside the Breathing Bag, the fish or animals inside will not run out of oxygen.

    Carbon dioxide exits the bags at 4 times the rate oxygen enters the bags, thereby constantly purging the water of toxic carbon dioxide, and allowing oxygen to replace it in the water. Kordon has shipped millions of bags around the world (termed “Sachets”) containing living foods (tubifex worms, brine shrimp, daphnia, glass worms, etc.) for aquarium fishes using the Breathing Bag technology. Hundreds of thousands of Breathing Bags have been used successfully to ship fishes, coral reef animals, and aquatic plants.


    Prior to the invention of Breathing Bags, the only plastic bags available for shipping fishes and aquatic invertebrates were made of polyethylene and had created a non-porous “solid-film barrier bag”. There was no porosity-mechanism to allow the passage of gasses through the bag wall. When using these “barrier” bags any oxygen required to sustain the life of the fish or other aquatic life inside the bag must – of necessity – be added as a gas inside the bag prior to sealing.

    This process has many problems.

    1 – High concentrations of oxygen can cause flammable conditions.

    2 – The presence of oxygen gas inside the bag takes up a lot of valuable shipping space.

    3 – Once the supplied oxygen is used up there is no more available – fish can quite literally drown in traditional old-fashioned “barrier-bags”.

    4 – A bag partially full of water with the rest filled with oxygen allows the contents to slosh during transport, stressing and possibly injuring fishes.

    5 – Toxic carbon dioxide from the fishes’ breathing builds up in the water, displacing the oxygen. The oxygenated air in the bags may not be satisfactory for fishes’ breathing, because (particularly from sources in underdeveloped countries), the bottled oxygen may be contaminated.

    IT IS TIME FOR A CHANGE: Time in the bag has always been the cause of losses in shipping live fish. With old, traditional air-chamber bagging methods there has always been a short time span between bagging the fish and getting safely to their destination. You typically have a short time span allowed before the air in the bags is depleted of all available oxygen and the fish begin to deteriorate. Long distance fish shipping using the old methods has always required periodic opening of the bags and adding of new oxygen. With Kordon Breathing Bags fish have been sealed into bags and sent on long transfer trips that have lasted for 7 to 10 days with no re-bagging and no addition of oxygen. The fish shipments have repeatedly arrived at their destination with very low losses and healthy, non-stressed fish. The continual flow ow carbon dioxide out of the bag and oxygen into the bag allows for safer shipping no matter how far the distance.

    In comparison – using the Kordon Breathing Bags allows for no sloshing and no stress. The Breathing Bags are sealed with as little air inside as possible. Ideally only water touches the inner surface of the bag. No air chamber of added oxygen means no slosh-zone and turbulant travel for the fish inside. You can test this by laying a filled Breathing Bag on a flat surface and allowing the fish to settle down. Picking up one edge of the bag – you can roll it until it is totally reversed – upside down – yet the fish inside will not move at all. No sloshing, no jiggling. no stress. Less stress equals less losses or injuries during shipping or transfer of live fish.

    Item No. 50201 – Breathing Bagв„ў 7″ x 14″ (full case is 2000 pieces)

    Item No. 50202 – Breathing Bagв„ў 9″ x 16″ (full case is 2000 pieces)

    Item No. 50203 – Breathing Bagв„ў 12″ x 19″ (full case is 1250 pieces)

    That betta fish you picked up at your local pet store may look pretty swell in its fishbowl, but ever wonder where it came from?

    One Reddit user, who claims to work at a pet store, shed some light on how bettas are shipped from fish suppliers in a striking photo series.

    Posted Monday, the images show a shipment of betta fish as they arrive in a cardboard box. Close-up photos illustrate how each fish is individually packaged — likely because males cannot be stored together without fighting — in a small plastic bag that contains a minimal amount of liquid with an unusual bluish tint.

    (Story continues below)

    Though we couldn’t get in touch with the user, several retailers confirmed that the practice depicted in the photos is commonly used to transport living fish through the mail, especially over long distances.

    Bryan Epstein of Florida-based retailer Blue Betta USA speculated that the product used to maintain and subdue the fish is probably Ship Right, or a similar water-conditioning and fish-calming solution.

    “We use a tranquilizer/stress reducer to ship fish. Depending on the size and type will dictate the size of the bag, amount of water and pure [oxygen],” Epstein wrote in an email to The Huffington Post.

    While there are no overarching regulations governing live fish shipments, shipping providers often set their own guidelines for mailing packages that contain live animals. The U.S. Postal Service, for example, requires senders to double-bag fish using strong plastic bags with a minimum thickness of 4 mils. Each bag must also be filled with about one-third water and the rest oxygen.

    “This sort of packaging is more typical of large scale fish farms in Asia shipping to pet store chains,” Victoria Parnell-Stark, who sells the siamese fighting fish and runs betta fan site Betty Splendens, clarified in an email to HuffPost. “This is not at all how hobbyists and most show breeders/distributers would ship bettas.”

    Dan Stearn, the owner of The Fish Store in Seattle further explained that the shipping method is often used because betta fish can breathe air, meaning they can survive in an oxygen-depleted atmosphere.

    “Many suppliers, particularly ones in Asia try to reduce the volume of water with their animals as much as possible to save on shipping costs because too many retailers and wholesalers here in the U.S. have complained about the shipping cost of the extra water,” Stearn told HuffPost. “There are many retailers and wholesalers around who do prefer the extra water since it ensures a healthier animal, but our requests for larger volumes tend to fall on deaf ears.”

    Despite the shipping conditions, which some may perceive as cruel, Stearn assures that the practice “has very little, if any, impact on the betta.” After all, fish may not even feel any pain. As one recent study suggested, a fish’s brain may not be big enough to allow the animals to process pain the way humans do.

    However, People for the Ethical Treatment of Animals still denounces the practice.

    “Most fish are cruelly transported from dealers to pet stores in tiny, cramped bags and containers that bear no resemblance to their natural habitats. Because of this, their water often contains a blue-tinted tranquilizing agent meant to reduce their agitation while they’re jostled about in bumpy, often days-long rides and hauled from one end of the country to the other,” PETA Senior Media Officer Wendy Wegner told HuffPost.

    Though bettas are most commonly characterized as aquarium-dwelling fish, the animal rights organization recommends that prospective buyers let the fish remain in their wild homes — shallow bodies of water in Asia — and choose not to support pet stores that sell them.

    Learn more about shipping live fish in PETA’s video investigation below.