Shipping Tropical Fish

Uniheat Shipping Warmer Heat Packs

With a little care and attention, you can get the best out of your Uniheat shipping warmers and ensure your tropical fish arrive in excellent condition. As the winter months are upon us, the following shipping method may be used as a guideline. Modify the method to your requirements but always pre test your shipping method before shipping your tropical fish.

Uniheat Tropical Fish Shipping warmerThere are too many variables to predefine a set packing method, not limited to but including, shipping box construction and heat conservation properties, livestock temperature requirements, shipping duration, ambient outside box temperatures, water volume within the shipping carton etc.

Use the following as a guideline for shipping tropical fish:


When the shipping warmer heat packs are removed from the package and exposed to oxygen in the air, a chemical reaction takes place with the contents of the heat pack, generating heat.

Before beginning to pack the tropical fish, the first job is to carefully remove the shipping warmers from their packaging, shake and gently knead the contents for around thirty seconds. The shipping warmers take a couple of hours to reach full operating temperature.

Heat Pack Warming

Place the shipping warmers in the fold of a towel or in your pockets.

The shipping warmers may not heat up properly if left on the side.

Heat Pack

Tropical Fish shipping Carton

Pictured is a pretty standard tropical fish shipping carton, of polystyrene construction.

Used by most tropical fish importers and exporters worldwide, as well as in country wholesalers and retailers.

This one has a cardboard outer for extra thermal properties and an interim polythene liner.

Flat pack insulated shipping cartons are also available here: shipping cartons.

Lining the tropical fish shipping carton

Due to the harshness of the Uk winter environment, the shipping carton has been lined with newspaper to provide extra thermal properties.

This also aids uniform heat dispersion throughout the shipping carton from the heat pack source. In extreme weather conditions, newspaper can also be added between the polystyrene outer and cardboard inner.

Tropical fish bagOk, it's fish bagging time! Scrimping on fish bags for shipping is seldom cost effective. Watertight fish bags can be purchased here. These bags are of clear polythene, 200 -250 gauge in various sizes.

Oxygen is a desirable commodity when bagging fish. In the UK oxygen bottles can be rented quite cheaply from your local BOC

Always at least use two tropical fish bags, a single leaking bag may cause the loss of the whole shipment as soggy heat packs don't work! Taping up the corners of the tropical fish bags will stop fish getting trapped whilst being shipped.

Troical Fish In Transit


The fish have now been added to the shipping carton. All the tropical fish bags have been secured at the top with two heavy duty rubber bands.

The top of the bag is simply twisted then folded back on itself before adding the rubber bands.

The bags have not been inflated to the extent that they are presurised. This will avoid bags bursting in transit.

Tropical Fish

A final single sheet of newspaper is placed over the top of the fish bags to aid uniform heat desperation.

Finally the shipping warmer heat packs are removed from the fold of the towel or pocket. If they were removed from the packaging a couple of hours previously, they should now be approaching operating temperature. Remove, and gently knead the contents one last time.


On the shipping warmer heat packs are one to three red stripes depending on the pack duration. These red lines must not be covered. The red lines contain perforations that regulate and allow oxygen to the pack contents. If the red lines are covered the pack will cool.

Tropical fish Shipping WarmerIf the shipping warmer heat packs are placed directly in contact with the fish bags, the fish will be subjected to extremes in temperature that some will not tolerate. The aim is to provide a comfortable environment, free of major temperature variations to ensure the livestock arrives in perfect condition.

Here the shipping warmer heat packs have been securely taped to the underside of the shipping carton lid, red indicator stripes un hindered.

The lid is then taped to the carton, and the cardboard outer taped up.

As mentioned previously, heat packs rely on oxygen to generate heat. In heavily laden tropical fish boxes, the air gap may be insufficient to support the heat pack or packs throughout the total destination period.

If you think this may be the case, take a look at how reptiles are shipped. Both the reptile and the heat pack require oxygen in transit!

Perforate the cardboard outer and shipping carton with two small holes on opposite sides a third of the way down to ensure optimum heat pack performance. This is easily done with a philips screwdriver and should obviously be performed before adding the fish bags!

Other packing tips.

Do not feed tropical fish for at least 24 hours prior to shipping. If you do, they will produce ammonia in the bags that may kill them. It goes without saying that the shipping water must have no Ammonia, Nitrite and acceptable levels of Nitrate for the particular species.

Also a point to note is the term posting tropical fish. UK Royal Mail will only accept the posting of fish fry. Some overnight Companies will also exclude the posting of tropical fish via their services, always check before posting / shipping your tropical fish.

JAT Clothing LTD Registered office Unit 6 St Johns House, Clyde Street, Bingley, BD16 4LD

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