Eel farming

Eel nursery and grow-out, indoors.

Eels need warm, steady water, shallow tanks and frequent grading. Two eel projects delivered: an 11-tank nursery in Japan inside a building that could not be dug, and a 720 m³ upgrade in Shaxian, China.

2

delivered eel projects

240 m³

nursery, Japan

720 m³

upgrade, Shaxian

24–26 °C

published optimum

Tahapan

Each stage needs a different tank.

European eel farming today is mainly done in recirculation systems, with water held steady around 24 °C (). Eels are stocked by tank floor area, not volume, because they live on the bottom. These are the published stage figures.FAO, European eel culture

Tahap
Ukuran
Tank
Density

Glass eel, quarantine

About 0.33 g

Small tanks, 3–4 m²

10–15 kg/m²

Juvenile

From about 5 g

6–8 m²

50–75 kg/m²

Pembesaran

Stocked at about 50 g

Square or round, 25–100 m²

Up to 100–150 kg/m²

Market

120–180 g or 300–600 g for smoking; about 150–200 g for kabayaki

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—

Density per m² of floor. We design eel tanks shallow and wide, so the floor area does the work.

Suhu

Warm and steady, all year.

The published optimum for heated eel farming is 24–26 °C (). In a closed loop that means the building and heating are part of the design: an insulated hall, limited make-up water, and heat recovered where it can be.FAO, European eel culture

Eel nursery RAS tanks in Japan with a worker inspecting
Pengelompokan ukuran

Eels grow unevenly, so you sort them often.

Individual eels grow at very different rates. Published practice is to grade about every 6 weeks, and to stop feeding at least 1–2 days before grading or harvest (). The layout has to make that easy.FAO, European eel culture

Design choice
Alasan

More, smaller tanks

Room to split each grade

Easy access to every tank

Grading every 6 weeks is a lot of handling

Separate nursery loop

Glass eels quarantined from grow-out stock

Drains and screens sized for eels

Eels escape through gaps other fish cannot

Eel nursery RAS tanks in Japan with a worker inspecting
Jepang

11 tanks in a building that could not be dug.

The Japan eel nursery sits inside a building where excavation was not possible. We fitted 11 tanks and the treatment loop into it without digging.

Running it

When an eel system goes wrong.

Symptom
Usual cause
Periksa

Wide size spread

Grading too infrequent

Grading every 6 weeks

Poor feeding in the nursery

Temperature unstable, or weaning too fast

Temperature log; weaning plan

Eels found outside tanks

Gaps at drains, screens or lids

Screens and covers

Losses after a new batch

Disease brought in with glass eels

Quarantine; UV on the nursery loop

Heating bill high

Too much make-up water

Water exchange; insulation

Why buy it from us

Eel projects in two countries.

Nursery and upgrade

A nursery in Japan, an upgrade in Shaxian.

Fits your building

Japan: no digging, 11 tanks fitted in.

Made in our factory

Tanks, drum filters, MBBR and UV.

On site to start-up

Engineers stay until the biofilter is running.

Proyek yang telah diselesaikan

Eel projects we delivered.

11 tanks inside a building that could not be dug

Japan · Volume240 m³ · SpeciesEel · TypeNew build
Jepang

720 m³ eel RAS upgrade, Shaxian

Shaxian, China · SpeciesEel · TypeUpgrade
Shaxian, China
FAQ

Eel questions.

Yes. Our Japan project is an eel nursery. Glass eels start in small quarantine tanks; published practice is 3–4 m² tanks at 10–15 kg/m².

The published optimum for heated eel farming is 24–26 °C, held steady.

Eels live on the tank floor. Published grow-out densities are given per m² of floor, up to 100–150 kg/m².

About every 6 weeks, because individual growth varies widely.

Yes. Our Shaxian project is a 720 m³ eel upgrade.

Yes. In Japan we fitted the farm into a building that could not be dug.

A first layout comes back in 3 days, free.

Belut

Send your building and output. Get an eel layout.

Stage, target output and the building. A first layout comes back in 3 days, free.