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The Water Filtration Machine is a Habitat Compartment that gives the player a stable and consistent supply of water and salt. It can be constructed with the Habitat Builder and placed on a wall in a Multipurpose Room or Large Room.


The Water Filtration Machine utilizes Energy from the Seabase to desalinate the ocean water, producing Salt and Large Filtered Water. It takes about 15 minutes and 40 seconds to produce one Large Filtered Water and 7 minutes and 40 seconds to produce one Salt. The Water Filtration Machine uses 0.85 points of Energy per second, or 51 Energy per minute (taken two or three at a time), and thus can be powered nonstop with four Solar Panels above 100m depth or almost nonstop with one Bioreactor.

When added to a base, the Water Filtration Machine will lower the Hull Integrity by 2.0 units. 

The Water Filtration Machine can store two pieces of salt and two bottles of water. This means that if the player takes out the water but leaves the salt inside, it will continue to generate water but not generate any more salt. It will stop working once its inventory is filled. 

The Water Filtration Machine can be built above water but will produce no salt and will produce water at 1/8th of the speed below water.

If powering the Water Filtration Machine with a consumable energy source such as the Bioreactor, note that each Large Filtered Water takes 799 energy to produce. This means that the Water Filtration Machine will consume 1,598 energy when left unattended.

If you grow Frost Vase Plants you can use them along the Salt to make Water Purification Tablets, which in turn can be used with Snowballs to make additional Large Filtered Water bottles, thus doubling the yield.


The blueprint for the Water Filtration Machine can be scanned in Omega Lab or Outpost Zero. It is crafted with the Habitat Builder.

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Databank Entry

Water Filtration Machine

The filtration system draws water unfit for human consumption from an external source, atomically splits it into its constituent parts, and outputs consumable liquid water and salts, while disposing of any harmful by-product. It can be built in any compatible habitat module, but has substantial power requirements.

'The Alterra Water Filtration System: Any liquid into pure, refreshing, pH-balanced water? Yes sir, ANY liquid!'

Source: Unlock the Water Filtration Machine