One of the most powerful and important upgrades you can make to your equipment in [Subnautica 2](https://www.rockpapershotgun.com/games/subnautica-2) is to increase your max Oxygen supply. When you begin the game, you are limited to a maximum of 45 seconds of breathable air before you start to drown. There are ways to top up your air supply during a dive (including Oxygen-emitting plants, and sacrificing the air in your Air Bladder for an extra Oxygen boost). But in reality, your progress will be severely limited until you craft yourself an Air Tank to boost your Oxygen supply.
In this guide, I'll walk you through everything you need to get in order to craft the three most important Oxygen supply items: the Standard Air Tank, the High Capacity Air Tank, and the Rebreather. Each of these serves as a massive progression milestone, and it's worth completing all the steps below as quickly as possible in your playthrough.
[Read more](https://www.rockpapershotgun.com/subnautica-2-how-to-increase-oxygen)