The Blood Kelp Trench is located south-west from Lifepod 5, between the Dunes, the Sparse Reef, the Grassy Plateaus and the Sea Treader's Path. A cave opening that leads directly to the Lost River Precursor Cache can be found in this biome.
The Trench lacks the Crabsquids and the Ghost Leviathan of the Northern Blood Kelp Zone, but still has predators in the form of Blighters, Ampeels, and Warpers. The more confined spaces may make it more difficult to avoid them if one is not careful.
It consists of a single deep trench with natural rock bridges spanning from one wall to another, and a small cavern system located below the Bloodvines where their roots can be found. One of the Wrecks can be found in this area, stuck between the trench's walls. This zone is nearly impossible to explore with the Cyclops due to the trench's narrow width.
Two corridors leading to the Lost River can found in this biome.
The Northern Zone can be found to the north of Lifepod 5, in-between the Northwestern Mushroom Forest and the Underwater Islands. This zone is considerably larger than the Trench, albeit being more exposed to the surface and not as deep.
Unique to the Northern Blood Kelp Zone are Crabsquids and a single adult Ghost Leviathan, as well as small "underwater islands" supported by Ancient Floaters and Bloodroots. This biome is littered with Quartz.
The Northern Blood Kelp Zone also harbors an Alien Cache, which is located in the deeper areas of the biome.
A corridor leading to the Lost River is located in the Northern Blood Kelp Zone.
- Both Blood Kelp Zones have entrances to the Lost River.
- The lack of pigmentation in fauna and flora present is an evolutionary trait often seen in deep sea lifeforms. This is due to the high resources pigment requires to be produced and the lack of such resources in deep sea environments.
- The lack of sunlight also creates an absence of pigment, due to the absence of harmful UV-radiation.