Koi care tools and calculators
This page brings together every XpertsPet tool for koi: 16 in all, across 9 topics including age, behavior, breeding, cost, health and housing. Pick a topic above to see its tools, or read on for a quick guide to what each group does and where to start.
Koi at a glance
A healthy koi usually lives 25 to 40 years, so the care decisions you make now play out over a long time. Koi are omnivores, which shapes what you feed and how much. They reach maturity at about 3 years old.
Koi are pond fish, not aquarium fish. They need a minimum of roughly 3800 liters, at least 1.2m depth for overwintering, and heavy biological filtration to cope with their waste output.
The health problems vets see most often in koi include koi herpes virus, ulcers and bacterial infections, anchor worm and fish lice and ammonia spikes in spring.
Koi quick facts
| Measure | Koi |
|---|---|
| Typical lifespan | 25–40 years |
| Diet | Omnivore |
| Mature at | About 3 years |
| Clutch size | 50000–100000 eggs |
Where to start
- Thinking about getting a koi? Start with the cost tools to see what you are signing up for.
- Setting up a home? The housing calculators size the space and work out how much bedding or substrate you need.
- Unsure about feeding? The nutrition tools give a daily amount you can adjust as you go.
- Raising a young koi? Use the weight and growth tools to check it is on track.
- Caring for an older koi? The age tools show its life stage and what usually changes next.
Other fish & aquatics
If you keep more than one kind of animal, there are tools for goldfish, betta fish, guppy and molly. You can also browse every pet on XpertsPet.