As Subnautica: Below Zero promises players that they'll be diving deeper than ever before, it's only natural that a majority of the game takes place underwater. Despite this, at the start of the game players can only spend so much time underwater, but there is a way to remedy this issue. By crafting an Oxygen Tank at the Fabricator, players can increase their O2 reserves allowing them to dive even deeper or simply stay underwater for longer. There are several levels of Oxygen Tanks, but players should work on just getting the Standard Oxygen Tank first and tackle its upgrades later on.
Like many items in Subnautica: Below Zero, players will need to use the Fabricator in order to make the Standard Oxygen Tank. The recipe for this device is unlocked automatically at the start of the game, but beginners may have a hard time tracking down everything they need to make it.
In order to fabricate a Standard Oxygen Tank, players will need two Titanium and one Fiber Mesh. For the Titanium, players simply need to search the nearby area for outcrops. Titanium is one of the more common metals in the game and can drop from Limestone, Argentine, Calavarite, and Galena outcrops. These don't require tools to break, so players can do this as soon as they start the game. In the case of Fiber Mesh, players need to fabricate this from two Creepvine Samples, and getting these is a process in and of itself.
In order to harvest Creepvine Samples in Subnautica: Below Zero, players will first need to craft a survival knife. This is done by combining Silicone Rubber with Titanium. Players should already know where to get Titanium from at this point, but Silicone Rubber is fabricated by getting Creepvine Seed Clusters. These simply require the player to approach the red bulbous seed pods on a Creepvine plant and harvest them. After making the survival knife, head back to a Creepvine plant and use the knife to get at least two Creepvine Samples. These can then be used at the fabricator to make Fiber Mesh.
With both the Fiber Mesh and Titanium, players can now craft the Standard O2 tank. This will increase their oxygen levels from a mere 45 all the way up to 75, providing a bonus 30 to their maximum. Players can now dive much deeper or stay underwater for longer, but there's still room for improvement. As players continue on through the game, they'll eventually unlock the recipe for High Capacity and Ultra High Capacity O2 tanks.
Subnautica: Below Zero is available now on PC, PS4, PS5, Switch, Xbox One, and Xbox Series X.