Lower Ocean

* Seawater below 500m in any zone or current except for polar is known as Lower Ocean. It begins below 500m with the thermocline/halocline layer - in which the water rapidly becomes cold with quite low salinity - and the Oxygen Minimum Zone. Here, it is oxygen-poor, high pressure and has almost no sunlight, so appears very dark; there is no red light at all, and what remains of the sunlight is faint and scarce. Therefore, there is no UV radiation. However, there are high detritus levels and it is very nutrient-rich. The OMZ ends at 1000m deep, where it is oxygen-rich, but at this point there is no sunlight at all; the rest of the ocean is the Midnight Zone. These conditions then continue another 500m to 1500m deep, when the pressure is very high and the detritus levels are low. At 3000m deep, the pressure is very very high and the detritus levels are very low. At 6000m, the pressure is extremely high and the detritus levels are extremely low. The pressure is absurdly high at 8000m deep and onwards.

### **Ecosystem/s:**

* 500 - 1500m: On the seafloor, Spongichonus adversus, Acanthrosfungarus sloanii, Scleracludas magnalba and Gorgonia mensus grow. Polypastilus praedatori also lives attached to the seafloor, filtering and even catching small animals. Ostracoderma kinifolis and Ostracoderma densissima additionally filter on the seabed as Lepirhampos ubivermis scoots around, filtering meat. In the water column, Regemsitula rhopalium, Masticephalus scintillamus, Thalakelphus narefaciemis - which only lives down to 800m - and Lampsichelus hippocratesii filter. Elinopterus oceanus and Elinopterus carelli consume Spongichonus and Acanthrosfungarus, alongside Euskulus wickhami, as does Dolophonaskulus rhinocerosai which additionally hunts Lepirhamphos and Euskulus. Lampsibathyus sirenus eats Masticephalus. Parateuthis venator, which only lives down to 800m, preys upon Dolophonaskulus.
* 1500 - 3000m: On the seafloor, Reumaplasmus abyssi, Acanthrosfungarus cactusi, Scleracludas magnalba - until 2000m deep - and Chionanthropus abbasei - below 2000m - filter. Polypastilus praedatori also lives attached to the seafloor, filtering and even catching small animals. Ostracoderma kinifolis and Ostracoderma densissima - down to 2000m - and Chelaeus altumis additionally filter on the seabed as Lepirhampos ubivermis scoots around, filtering meat. In the water column, Regemsitula rhopalium, Masticephalus multiminimacrura and Lampsichelus paladarus filter. Elinopterus oceanus consumes Reumaplasmus and Acanthrosfungarus, alongside Euskulus wickhami, as does Dolophonaskulus attenboroughei which additionally hunts Lepirhamphos and Euskulus. Lampsibathyus sirenus eats Masticephalus.
* 3000 - 6000m: On the seafloor, Reumaplasmus altumi, Acanthrosfungarus cactusi and Chionanthropus abbasei filter. Polypastilus praedatori also lives attached to the seafloor, filtering and even catching small animals. Schedocavoura reevis additionally filter on the seabed as Lepirhampos ubivermis scoots around, filtering meat. In the water column, Regemsitula rhopalium, Masticephalus multiminimacrura and Lampsichelus paladarus filter. Elinopterus oceanus consumes Reumaplasmus and Acanthrosfungarus, alongside Euskulus wickhami, as does Dolophonaskulus attenboroughei which additionally hunts Lepirhamphos and Euskulus. Lampsibathyus sirenus eats Masticephalus.
* 6000 - 8000m: On the seafloor, Reumaplasmus altumi and Acanthrosfungarus cactusi filter. In the water column, Regemsitula rhopalium filter.
* 8000m+: Nothing lives here.