Finding an Acidic Raion Pouch is one of your first goals in Subnautica 2, since you'll need it to make the basic battery required for a scanner. And the scanner is arguably your most important tool, since it's used to unlock more blueprints, like the Wakemaker and Sonic Resonator.
Luckily, you don't actually have to go too far to find Acidic Raion, and once you know where to look, you can keep going back for more as it respawns periodically. Just note that you need to craft a Survival Multitool and bring it with you to harvest it, though I'd be surprised if you left this essential tool back at base.
How to get Acidic Raion Pouch in Subnautica 2
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