One of the most pressing issues when you start playing Subnautica: Below Zero will be simple survival. You will need to instantly start getting water or you will run into problems. At first, players will need to farm the right kind of fish to get water. The fish in question is the Bladderfish. This purple and pink fish can be found swimming around outside the pod, and is easy enough to grab with your hand. Swim up to it and interact with it to grab it. Just make sure you select and empty tile on the toolbar, or your next interaction will free the fish.