Planet Zoo 2 Koi: Aquarium Care, Shoals & Breeding

Aquarium or exhibit: which values does this page use?

Frontier lists Koi for both aquarium and exhibit placement. The numeric record captured here is explicitly the aquarium model. Its area, population and reproduction fields must not be presented as a separate specification for an exhibit tank.

Choose the placement first. For an aquarium, use the environment fields below and verify the result in the game. For an exhibit, follow that enclosure’s own setup and welfare controls rather than copying the aquarium area values. The animal database identifies the other species with dual placement.

Koi aquarium-model requirements

The captured aquarium model has no terrain-percentage entries and no barrier-grade or minimum-height field. Missing fields are not zero requirements. Use the aquarium construction controls and the animal’s current welfare panel for those checks.

Do not turn the population range into a fish count

Koi are flagged as shoaling fish. The record’s minimumPopulation value is 1 and maximumPopulation value is 5, but this page does not equate those numbers with individual visible fish or invent a fish-per-shoal conversion.

Likewise, the stored 15 m² additional-animal field is reproduced as a source value, not multiplied by the number of fish you can see. Use the game’s shoal and population controls to understand the unit being added, and verify the resulting space and welfare readings after each change.

The aquarium planner can help compare published fields, but a shoal-specific total requires a verified game-unit interpretation. A calculated total without that interpretation would be misleading.

Set up a freshwater Koi aquarium

1. Select aquarium placement if you want to use these care fields. Build the tank, add a staff gate and connect it to a usable path.
2. Attach filtration, select freshwater and set temperature within 18–25°C. Use the aquarium guide for network and maintenance controls.
3. Inspect the 50 m² minimum deep-swimming field in the game’s enclosure panel, without substituting a tank-volume figure in litres.
4. Add Koi through the game’s shoal-aware controls. Read the population and space response before increasing the group, then check the individual or shoal welfare categories the game exposes.

Can Koi live with Common Rudd?

Common Rudd is the one Neutral relationship listed in the captured Koi record. No Thriving relationship is listed. Neutral does not mean the pairing supplies a Thriving bonus, nor that the water and space needs of either species can be ignored.

Compare Common Rudd’s own entry in the animal database before planning a shared tank. The Koi record does not establish compatibility with every freshwater species; matching freshwater alone is not enough to add another animal to a confirmed-pairing list.

Koi breeding fields and what is missing

Do not fill the missing litter-size field with a real-world egg count or a guessed number of visible fish. The aquarium-model capture also does not publish male/female mixed-group caps or bachelor maxima for Koi.

The game’s Easy label and short gestation/incubation field do not guarantee a particular number of offspring. Check maturity, the current breeding controls and the game’s shoal-population handling. These are game-data timings, not biological care guidance.

If the Koi setup does not match the table

Koi are a different planning problem from a solitary large aquarium animal such as the West Indian Manatee. Their smaller published area field does not remove the need to understand shoal units and placement-specific care.

• Check placement first: exhibit controls are not the aquarium model described here.
• Verify freshwater and an actual temperature inside 18–25°C.
• Read the unit used by the game’s shoal/population panel rather than counting fish in the viewing window.
• Inspect accessible deep swimming space after layout or group changes; do not assume the stored minimum is a complete tank blueprint.
• Use the current welfare panel for food, enrichment, health and any requirements absent from the snapshot.