Name: 15-18cm Japanese Butterfly Koi Tosai Koi Mix
Brand: Byer Koi Farm
Price: 90.0 GBP
Availability: InStock

15-18cm Japanese Butterfly Koi Tosai Koi Mix

Byer Koi Farm

£150.00 £90.00 Save £60.00

Tax included.

END OF SEASON SALE: These small koi mixes offer particularly good value as we reduce our remaining stock. You’re welcome to tell us about any preferences when ordering, and we’ll do our best to accommodate them. However, availability is more limited at this stage of the season, so particular varieties, colours or individual koi cannot be guaranteed.

Please note that, due to the popularity of this mix throughout the season, the photographs shown were taken earlier this year and are intended to illustrate the type and variety of koi available, rather than the exact fish currently in the tank. The current mix remains a colourful selection selected from the fish available at the time of ordering.

These Japanese Butterfly Koi have been selected from two of Japan’s best-known producers of longfin koi — Yamasan Koi Farm and Suda Koi Farm.

With their flowing fins and bright metallic colours, Butterfly koi are a striking addition to any pond. This mixed selection includes koi from both breeders and offers a varied mix of colours and patterns.

Many of these koi were introduced in our recent blog about Suda and Yamasan Japanese Butterfly Tosai arriving for Spring 2026.

Each koi measures approximately 15–18cm.

Online orders are selected personally by Adam or Amanda, using our experience to choose a balanced and attractive mix from the tank.

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Koi delivery is via a specialist overnight fish courier service that we have been using successfully for many years.

Local pickup is available; choose that option in the checkout process, then once purchased, contact us to arrange collection.

For dry goods, the vast majority of items ordered before midday are shipped the same day, on an overnight service.

Byer koi farm

UK breeder of champions

Pushing the boundaries is in our DNA, and now with Byer Koi Farm being a leading UK koi farm consistently producing champion winning koi, we are elevating the quality and perception of UK bred koi and contributing to the success of UK aquaculture

everyone contributes

Byer Koi Farm is a family business

Everyone lends a hand in peak season. Harvesting fry ponds and manning our stand at koi shows are just a couple of areas where the kids muck in.

farming koi the japanese way

Selection, selection, selection! Only a tiny proportion of each spawning makes the highest quality koi.

The year's we've spent optimising our breeding lines delivers better quality koi for our customers.

15-18cm Japanese Butterfly Koi Tosai Koi Mix

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