There are very diverse production methods for EU aquaculture species, some of the main ones are the following (STECF Aquaculture economic data table, 2023):
Ponds: bodies of water, either natural or man-made, that hold water for activities like raising fish. They can be used for freshwater aquaculture, to produce species such as common carp, silver carp, and pikeperch, among others and for marine aquaculture to produce species such as seabass, seabream, sole, and mullets.
Tanks and raceways: artificial structures designed to hold and circulate water. Typically constructed above ground, they can be made from various materials (e.g. bricks, cement, concrete, fiberglass, plastics, etc.) in various shapes and sizes. They can be used for both freshwater and marine water. Raceways are used mostly for trout, but can also be used for sturgeon, while tanks are used for a wide range of species, notably turbot.
Recirculation Aquaculture Systems (RAS): is a technology which reuses the water in production, they can be operated using both freshwater and marine water. RAS are based on the use of mechanical and biological filters as well as ultraviolet radiation (UV) lamps and Ozone treatments to clean the water. RAS are used indoors in hatcheries across the EU for producing eggs, larvae and juveniles. RAS can be used to produce salmonids, great amberjacks, and meagre. Shrimp farming in RAS in EU Member State is an emerging sector.
Enclosures: are specific areas in the water, like shallow lagoons near the coast, that are fenced off with nets, wood or concrete attached to the seabed permitting free water exchange. In enclosures fish can swim freely inside but cannot escape. Eel and other types of fish like seabass, seabream and mullet can be also farmed in this way.
Net pens: are enclosed structures that can be open or covered. They can be made of nets or any other material that allows the natural exchange of water. These structures may be floating or suspended, supported by metal, plastic, or wooden frameworks. Net pens can be used to perform fish farming in lake; however, they are mostly used to raise fish in the sea. Net pens for marine aquaculture can be moored together and anchored to the sea floor. Many types of fish are farmed in net pens, including sea bass, sea bream, meagre, Atlantic salmon, trout, greater amberjack and bluefin tuna.
Off-bottom systems: refer to various structures used mainly for species that can be produced suspended (mussels, oyster and seaweed) aquaculture. These systems include trestles, wooden supports and bouchots, which are inserted into the seabed and mainly installed in the intertidal and shallow subtidal zone (foreshore and lagoons), long lines, and floating raft (bateas), which are equipped with floats and anchored on the seabed. These moored structures remain in a fixed position while being able to adjust the water movement in more or less sheltered coastal areas. Off-bottom systems can be also used for macroalgae production.
On-bottom systems refer instead to farming organisms directly seeded on muddy or sandy areas in the intertidal zone or in the shallow subtidal zone. They can be used for species such as clams, and sea cucumber.
Open or closed-system bioreactors for microalgae.
In addition, during the early growth stages, most fish and algae species need to be in land-based facilities such as hatcheries and nurseries. Seeds of molluscs are produced in hatcheries or collected from the wild.