So, the first 30 minutes go like this. Find the stuff to make and craft the knife, scanner, fins, air tanks, and building tool.

You can eat kelp and make bleach>water w salt and coral to stay alive, though it's a LOT of kelp.

Then head straight to southern island to scan the multipurpose room, indoor and outdoor grow beds, and grab lantern fruit and marble mellons.

You can then build a base and grow all the food you will ever need. I stock up on a ton of bleach and make water as needed, though the food also restores some hydration.

I usually have this done before the Aurora explodes.

Once you have the cyclops you can plant in there as well. Three lantern fruit trees per base is all the food you will need in the game, and marble melons have a lot of water.

The only thing you miss out on really is the emergency air bladder, as that requires a fish. To make up for it I carry a second air tank when diving deep or exploring wrecks. I also build outdoor grow beds w brain corals in strategic places as emergency air supplies.

Honestly, I started it as a lark, and found it so enjoyable because I never get distracted chasing down and catching fish.