Alien Containment (Subnautica)

The Alien Containment is a large, cylindrical aquarium which can be filled with Fauna that has been caught or hatched by the player. It is built using the Habitat Builder inside the Multipurpose Room. The blueprint can be retrieved via a data box.

Building
In order to get inside of or put fish into the Alien Containment, the player must build a Hatch on one of the sides. The player can then enter the Alien Containment and release caught fish into it. Non-edible fish can be added through the use of their respective eggs. If two or more Multipurpose Rooms are stacked on top of each other, building Alien Containments inside each room will cause the Containers to merge into one bigger tank.

Uses
If the player leaves two creatures of the same species inside the Alien Containment for long enough, they will breed and another fish of the same species will spawn inside. Once the Alien Containment reaches a population of ten fish, the reproductive process will stop. If more fish are added after the maximum is reached, some will die and float to the top of the container. Multiple Alien Containments stacked on top of each other will increase the amount by ten each.

Eggs can be placed inside the Alien Containment. This can be done by simply dropping the Eggs inside the Alien Containment. Eggs will take about three to five in-game days (sometimes less) in order to hatch. When hatched, the fauna within the eggs will create smaller versions of said fauna, and will grow inside the Alien Containment. Non-edible Fauna can be bred this way to be used as fuel for the Bioreactor. Keep in mind that egg-laying fish will keep laying eggs (so long as there are two or more) and hatching them until the population cap is reached, as stated above.

Flora can be placed inside the Alien Containment, via a Planter UI with sixteen slots that appears when hovering above the soil. This can be used as an alternative to the Exterior Growbed for farming aquatic resources. Tiger Plants will attack certain fish if planted in the Alien Containment, potentially killing the fish and damaging the base. Creepvines will not grow to their full height without stacking Alien Containments.

Placing fauna infected with the Kharaa Bacterium into the Alien Containment will infect the other fauna after some time. However, this is just an aesthetic change and has no effect on the fauna.

Aggressive Fauna hatched inside the Alien Containment will have a Passive attitude towards the Player when they enter the Alien Containment, and if they are released into the wild. Aggressive Fauna hatched inside the Alien Containment will not attack other fauna inside the Alien Containment, but will attack other fauna if released into the wild, even other fish hatched inside the Alien Containment. Once released into the wild, Aggressive Fauna will also attack small player vehicles, regardless of whether the player is in them or not, although they lose interest much faster than their wild counterparts.

Plantable Flora
For a complete list of plantable flora, visit List of Plantable Flora.

Trivia

 * The former name for the Alien Containment was the Large Aquarium, and before that, the Water Park.