Subnautica 2 Food, Water and Oxygen Guide

First Survival Priority

You start Subnautica 2 with 45 oxygen and 100 health on Proteus. Your character also has Digestive Incompatibility — you cannot eat native fish or plants without penalty.

The first survival loop is: collect Water Slugs for hydration, find the Angel Comb to unlock proper eating, then craft oxygen upgrades to extend your dive time. Neglecting any of these three will kill you within your first few outings.

Water

Primary Source: Water Slugs

Water Slugs are translucent blue creatures found on the ocean floor near the Lifepod. Collect them and process at the Lifepod Fabricator (Sustenance tab):

Processed Water is far more efficient than eating Water Slugs raw. Stock up before longer trips — hydration drains faster than hunger in Subnautica 2.

Alternative Water Sources

Once you build a base with a Processor, you can produce additional water from plant matter, though Water Slugs remain the most efficient early option.

Food

Step 1: Unlock Digestion Adaptation

Your Lifepod storage contains a few Nutrient Blocks (+40 food each) to get you started. But to access the full food system, you must first unlock Digestion Adaptation:

1. Swim northeast from the Lifepod. Look for a large pink plant — the Angel Comb — and follow the signal if it is active
2. Interact with it to unlock Digestion Adaptation
3. After this, you can safely eat native fish and plants

The same area often has an Anita’s Blackbox waypoint from NOA that leads to the Angel Comb.

Step 2: Cooked Fish (Fabricator)

Once Digestion Adaptation is active, catch fish near the Lifepod and cook them at the Fabricator. Cooked fish is significantly better than raw:

Step 3: Advanced Recipes (Fabricator)

These recipes require additional ingredients but offer much better returns:

Cherimoya Rotsac can be found in shallow waters and gives +10 Food, +5 Water when eaten raw.

Healing

Healing items are essential when exploring deeper areas or after creature encounters. Keep at least one Basic First Aid Kit in your inventory.

Oxygen Management

Base Oxygen

You start with a short oxygen window. When it hits zero, you take damage and die quickly. Plan your return route before running low — do not rely on a last-second dash to the surface.

Air Tank Progression

• Silver for the Standard Air Tank is found in caves near Camp One, north of the Lifepod. This is a key early milestone — prioritize it.
• Plasteel Ingot requires a Processor in your base (2 Titanium + 1 Lithium).
• The High Capacity and Ultra High Capacity blueprints must be found through scanning.

Air Bladder

The Air Bladder (2 Titanium + 1 Rubber at the Lifepod Fabricator) serves two purposes:

• Provides emergency oxygen mid-dive
• Can rocket you to the surface for a rapid ascent

Carrying a second Air Bladder gives you a backup emergency option.

Natural Oxygen Sources

Oxygen Tunics — blue bulbous plants found throughout the ocean — release breathable bubbles when touched. Mark their locations as mid-dive refill points.

Rebreather

A Rebreather (2 Fiber Mesh + 1 System Chip) is a piece of diving equipment. Craft it when you start exploring deeper areas regularly.

Equipment Priority

1. Collect Water Slugs → craft Water at Fabricator (immediate hydration)
2. Find Angel Comb (large pink plant, northeast) → unlock Digestion Adaptation (enables food system)
3. Craft Standard Air Tank (requires Silver) → extends dive time significantly
4. Craft Air Bladder → emergency oxygen safety net
5. Build base with Processor → unlock High Capacity Air Tank and advanced crafting
6. Craft First Aid Kits → prepare for deeper exploration

Common Survival Mistakes

• Drinking raw Water Slugs — you lose food value. Always process them at the Fabricator.
• Ignoring Silver — you cannot craft the Standard Air Tank without it. Find it early.
• Not unlocking Digestion Adaptation — Nutrient Blocks run out fast. Get the Angel Comb early.
• Overextending without oxygen — always plan a return route. Mark Oxygen Tunic locations.
• Carrying only one Air Bladder — a second one can save your life in an emergency.
• Building a base before stabilizing food and water — solve your basic survival needs first, then build.

FAQ

How do I get water in Subnautica 2? Collect Water Slugs from the seafloor near your Lifepod and process them at the Fabricator into Water (+40 hydration each).

How do I get food without getting sick? Swim northeast from the Lifepod and find the Angel Comb (a large pink plant) to unlock Digestion Adaptation. After that, catch fish and cook them at the Fabricator.

How do I increase my oxygen? Craft a Standard Air Tank at the Lifepod Fabricator (2 Titanium + 1 Rubber + 2 Silver) for +30 oxygen (75 total). Upgrade to High Capacity later.

What’s the best early food recipe? Cooked Harvestmoon (+30 Food) and Cooked Geordie (+30 Food) are the easiest early options. Cooked Bluemoon (+25 Food, +5 Water) gives bonus hydration.

Water runs out faster than food — what do I do? Always carry several Water bottles. Craft them from Water Slugs before leaving the Lifepod. Hydration drains faster than hunger.

Where do I find Medical Gel Sacs? Harvest them from Acidic Raion plants using your Survival Multitool.

Next Steps

• Beginner Guide — full first-session walkthrough
• Where to Find Silver — needed for the Standard Air Tank
• Current Version — latest Early Access changes