Planet Zoo 2 How to Change Water Salinity
Water salinity in Planet Zoo 2 is controlled by the Aquarium's Filtration Network rather than the tank itself. Each network can provide Freshwater, Brackish, or Saltwater, and the correct setting depends on the aquatic species you intend to keep, so changing salinity means finding the Water Filter that serves the Aquarium and editing that network.
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How to Change Water Salinity
Freshwater, Brackish & Saltwater
Can't Change Salinity?
Check Water Filter Power
Check the Filtration Connection
Career Tutorial Problems
How to Change Water Salinity in Planet Zoo 2
To change an Aquarium's water salinity in Planet Zoo 2, select the Water Filter connected to the tank, open the option to edit its Filtration Network, and find the salinity setting currently displaying Freshwater, Brackish, or Saltwater. Change that setting to the water type required by the species in the Aquarium.
- Select the Water Filter serving the Aquarium.
- Open the option to edit the Filtration Network.
- Find the current salinity setting.
- Switch between Freshwater, Brackish, or Saltwater.
- Check the Zoopedia to make sure the setting matches your animal's requirements.
The setting can be easy to overlook because salinity belongs to the filtration system. Aquarium temperature, by comparison, is configured from the Environment tab of the Aquarium Info Panel when the Aquarium Staff Gate is powered.
Freshwater, Brackish and Saltwater Explained
Planet Zoo 2 Filtration Networks can treat Aquarium water as Freshwater, Brackish, or Saltwater. Aquatic species have specific salinity requirements, and Frontier recommends checking the Zoopedia before deciding which setting to use.
Do not choose a water type based simply on whether an animal lives in an Aquarium. Fully aquatic animals can require different salinity conditions even though they use the same general habitat type.
This also matters when designing a larger Aquarium system. Because the salinity comes from the Filtration Network, make sure the network serving a tank is configured for the animals actually living there rather than assuming one filtration setup will suit every aquatic species in the zoo.
Why Can't I Change Water Salinity?
If the salinity control will not change, start by checking the Water Filter itself. A Filtration Network relies on functioning filtration Facilities, and Water Filters require nearby power before they can operate normally.
It is also worth confirming that you are editing the Filtration Network rather than looking through the Aquarium's normal management tabs. The salinity selector is attached to the filtration setup, while other Aquarium controls such as temperature are handled elsewhere.
If the Water Filter is powered and the correct network is selected but the salinity option still appears unavailable, the problem may be with the current Aquarium or scenario state rather than the salinity setting itself.
Make Sure the Water Filter Is Powered
Water Filters are powered Facilities, so they need to sit within the range of a working power source. Without power, the Filtration Network cannot properly maintain the Aquarium.
If you are trying to switch from Freshwater to Saltwater or Brackish water and the network is not responding, check the facility's power status before rebuilding the Aquarium.
In Career Mode, this may mean placing the power Facility close enough to the filter while still respecting the scenario's available building area. One launch-day report from the Nordic Fjord Zoo tutorial described being unable to change salinity while the filtration system was also unpowered.
Check That the Aquarium Is Connected to the Filtration Network
Changing the Water Filter's salinity will only help the intended Aquarium if that tank is actually connected to the same Filtration Network.
Planet Zoo 2 connects a Filtration Network to an Aquarium through the node on the Aquarium Staff Gate. The filter itself must also have power, and the network needs enough Filtration Rate to meet the Aquarium's demand if you want water cleanliness to remain stable.
If you still need to set up that connection, the Planet Zoo 2 Water Filter connection guide covers the Staff Gate node, network setup, power, and filtration demand.
Career Mode Salinity and Filtration Problems
There have been launch-day reports of the Career tutorial getting into a state where a Water Filter could not be powered correctly and the player was consequently unable to change the water to Saltwater.
In one reported case, the player first tried replacing the filtration system but later ran into placement restrictions even when attempting to put it back in the same area. Restarting the Career scenario ultimately cleared the problem and allowed the filtration setup to work normally.
That does not make restarting the first solution. Check the network, power source, placement, and salinity control first. If the Career tutorial still refuses to let a correctly placed filtration system function, restarting the scenario is a reasonable last resort based on current player reports.
Salinity and Water Cleanliness Are Separate
Setting the correct salinity does not automatically mean the Aquarium's filtration needs are fully covered. The same Filtration Network also has to provide enough Filtration Rate to handle the Aquarium's water volume and animal population.
If filtration demand exceeds the network's available rate, Water Cleanliness will gradually decline even when Freshwater, Brackish, or Saltwater is set correctly.
That means an Aquarium can have the right salinity but still have a filtration problem. When diagnosing aquatic welfare, check both the selected water type and whether the network has enough capacity for the tank.
