At Cryospain we are proud to introduce a new project we have carried out to preserve and secure the oxygen used in the transport of fish for fish farms.

This type of transport is conducted with perfectly adapted trailers, featuring individual tanks where fish from the farms are placed to ensure a safe and comfortable journey for them.

Fish farms have undergone significant transformation in recent decades due to the adoption of advanced technologies aimed at improving production quality and efficiency. One such innovation is the use of cryogenic oxygen to oxygenate the waters.

Why use liquid oxygen?

A large amount of oxygen is needed to ensure a complete supply during transport. Storing the oxygen in a large tank would be impractical for road transport since it would take up much of the trailer, reducing space for the fish. The ideal solution is to use compact cryogenic tanks to store oxygen in a cryogenic state. These cryogenic tanks are known as Dewars, and thanks to their design, they take up little space and can be perfectly placed on trailer platforms.

Cryogenic oxygen is generally below -183°C and in this state occupies 1/860 (or 0.12%) of the volume compared to its gaseous state at atmospheric pressure and ambient temperature, which is the state of oxygen in the air that we breathe.

This means that, for example, 1 liter of liquid oxygen will expand to approximately 860 liters of gaseous oxygen at atmospheric pressure and ambient temperature. This ratio is why oxygen is stored and transported in its cryogenic form.

What is cryogenic oxygen used in fish transport tanks?

Cryogenic oxygen is used in fish farms to improve the amount of dissolved oxygen in the water. An adequate level of dissolved oxygen is essential for the fish’s health, optimal growth, and survival.

The lack of oxygen can cause stress in fish, leading to illness and increased mortality. By maintaining an optimal level of oxygen, a healthy environment is ensured for the fish, reducing the risk of disease and death.

A high level of oxygen in the water can also inhibit excessive growth of algae and harmful bacteria, keeping the water clean and reducing the need for chemical treatments.

 Although the initial investment may be high, the use of cryogenic oxygen can result in long-term savings. By reducing mortality, increasing production and reducing treatments, operating costs are significantly reduced.

How is cryogenic oxygen applied in water tanks?

Cryogenic oxygen is stored in special thermally insulated tanks (Dewars) and is vaporized before being injected into the water. It is crucial to ensure the uniform distribution of oxygen throughout the pond or tank.

Cryospain, experts in cryogenic engineering

Thanks to more than 20 years of experience in cryogenic engineering, Cryospain is an expert in the maintenance and development of cryogenic systems. Our latest project has been carried out for one of the largest aquaculture companies in Europe, with over 40 fish farms in southern France and northern Spain.

This large company has more than 20 transport trailers to transport Rainbow Trout (Oncorhynchus mykiss) from the fish farms to the processing center where they are prepared for commercialization. Rainbow Trout is highly valued for its benefits compared to other fish:

  • Rainbow trout are a rich source of high-quality protein, Omega-3, vitamins (such as B12 and D) and minerals (like selenium and iodine). These nutrients are essential for heart health, brain function, and overall metabolism.
  • Unlike some large sea fish, such as swordfish and tuna, rainbow trout have low levels of mercury, making it safer for regular consumption, especially for pregnant women and children.
  • They offer a mild and delicate flavor, as well as a tender texture, and are perfect for smoking.

Cryospain performs a complete inspection of the liquid oxygen Dewars used in the transport of Rainbow Trout. If necessary, we carry out the repairs needed to ensure their proper functioning and the most stringent checks to safeguard their correct operation. At Cryospain, we offer complete service, including vacuum recovery, leak checking, and safety element verification.

We perform an essential task in order to preserve all the qualities of this prized fish and its survival. By providing this critical service, we are ensuring the well-being of the fish at a critical moment, such as road transport of these vertebrate animals that need to be submerged in water to breathe the oxygen provided by the Dewars through their gills.

The Confidence of Choosing a Leader

Cryospain is one of the cryogenic engineering companies with the greatest international projection, with numerous projects related to cryogenic maintenance.

That’s why we offer all our clients our services for the maintenance, inspection and repair of cryogenic Dewars. To ensure the operability, safety, and efficiency of cryogenic equipment, which translates into economic, environmental, and safety benefits.

Don’t hesitate to contact us at

Contact us

Privacy Policy

Thank you! We'll get back to you as soon as possible.