This guide will let you know how to get the Orange Tablet in Subnautica.
Starting from the coral tube sticking up out of the water, you will need to make your way about two bumps to the left of the southwest until you come across a large hole in the Grand Reef.
It is recommended to have a sea moth with an MK2 depth module and perimeter defense, a sea glide, a high-capacity O2 tank, and a survival knife.
The two main threats you will encounter in the Grand Reef caves is the Crabsquid which can emp your vehicle/electronics, so you have to avoid it or use the perimeter defense against it. Some warpers can warp you out of your vehicle; you can run away from it or deal enough damage until it warps away or use perimeter defense against it.
The coordinates for this location are (-680, -515, -941).
While you don’t need the orange tablet to beat the game, if you want ot open the lost river cache, you will need the orange tablet to open the door.
Here is the large hole you are looking for.
Once you’ve gone down the hole and are in the cave, you will need to head North and come across a degasi base in the Grand reef caves.