Kohaku Koi Care Guide
The Kohaku koi (Cyprinus carpio) is one of the most iconic and popular koi varieties in the UK. Known for its simple yet striking red and white pattern, it forms the foundation of many koi collections.
In this guide, you'll learn everything you need to know about Kohaku koi care, including pond size, water conditions, feeding, compatibility, and typical UK prices - plus how to buy or sell them locally.
Quick facts about Kohaku Koi
Kohaku koi are defined by their white (shiroji) body with red (hi) markings. Despite their simple colouration, high-quality Kohaku are highly prized for their pattern, colour depth, and body shape.
They are one of the "Big Three" koi varieties, along with Sanke and Showa.
Cyprinus carpio
60-90 cm (can grow larger in ideal conditions)
Japan
1,000L+ (larger strongly recommended)
20-30+ years
Peaceful, social
4-28°C (coldwater species)
Omnivore (koi pellets, vegetables, natural pond foods)
6.5-8.0
£30-£500+ depending on size and quality
How Many Kohaku Koi Should You Keep?
Kohaku koi are social fish and should be kept in groups.
- Keep at least 2-3 koi
- Stocking depends on pond size and filtration capacity
- Allow generous space per fish
Overstocking can lead to:
- Poor water quality
- Stunted growth
- Increased disease risk
Long-term planning is essential due to their size and lifespan.
Ideal Pond Conditions for Kohaku Koi
Providing the right pond environment is key to maintaining both health and colour quality.
- Pond Size: Larger ponds (2,000L+) are strongly recommended
- Depth: At least 1-1.5 metres for temperature stability
- Filtration: Strong mechanical and biological filtration is essential
- Water Conditions: Clean, stable, well-oxygenated water
- Plants & Features: Marginal plants and shaded areas can reduce stress
- Aeration: Air pumps or waterfalls improve oxygen levels
High water quality helps maintain bright white skin and vibrant red patterns.
Compatibility with Other Fish
Kohaku koi are peaceful and mix well with other pond fish.
- Good Tankmates: other koi varieties, goldfish, and peaceful coldwater species
- Avoid: very small fish that may be outcompeted for food
They are non-aggressive but can be dominant feeders.
Are Kohaku Koi Easy to Care For?
Kohaku koi are moderately easy to care for with the right pond setup.
They require:
- Large, well-filtered ponds
- Regular maintenance and water testing
- High-quality diet
- Long-term commitment
They are hardy, but maintaining colour quality requires good conditions.
Kohaku Koi Price in the UK
In the UK, Kohaku koi typically cost between £30-£500+, depending on size, pattern, and quality. Show-grade or imported Japanese koi can cost significantly more.
Prices vary depending on:
- Pattern balance and symmetry
- Colour quality (deep, even red and clean white)
- Size and age
- Breeder and origin
They are one of the most widely available but also highly valued koi varieties.
Where to Buy Kohaku Koi in the UK
Kohaku koi are available from specialist koi dealers, pond centres, and breeders.
Sourcing koi locally can:
- Reduce transport stress
- Allow you to inspect pattern and quality
- Offer better value
TankMate UK helps connect pond keepers who want to buy, sell, or rehome fish safely - without shipping.
Can You Sell Kohaku Koi?
Yes - Kohaku koi are commonly sold or rehomed by hobbyists and breeders.
Selling locally is often the best option, as it:
- Minimises stress for the fish
- Avoids the risks of transport
- Connects you with knowledgeable buyers
TankMate UK allows you to list koi quickly and find local buyers.
Feeding Kohaku Koi
Kohaku koi are omnivorous and require a balanced diet.
Key Tips:
- Feed high-quality koi pellets as a staple
- Supplement with vegetables such as lettuce and peas
- Adjust feeding based on water temperature
- Avoid overfeeding
A high-quality diet helps maintain strong colour and healthy growth.
Common Problems with Kohaku Koi
Colour fading or poor pattern definition, often caused by:
- Poor water quality
- Low-quality diet
- Genetics
Poor water quality, linked to:
- Overstocking
- Overfeeding
- Inadequate filtration
Slow growth or poor condition, caused by:
- Insufficient pond size
- Poor nutrition
Why Kohaku Koi Are So Popular
- Classic red and white colouration
- One of the most recognisable koi varieties
- Highly valued by beginners and experts alike
- Wide range of patterns and qualities
- Foundation of many koi collections
When kept correctly, Kohaku koi offer timeless beauty and elegance in any pond.
Frequently Asked Questions
A white koi with red markings, one of the most classic koi varieties.
High-quality patterns, colour depth, and breeder lineage increase value.
Their colour can develop and improve with age and good conditions.
At least 1,000 litres, though much larger ponds are strongly recommended.
Looking to Buy or Sell Kohaku Koi Locally?
TankMate UK connects pond keepers who want to buy, sell, or rehome fish safely within their local area.
Whether you're stocking your pond or passing fish on to a new home, you can:
- Browse fish available near you
- List your own fish in minutes
- Avoid the risks of transport