OiOI Koi Logo

Launch Offer – 10% off Evolution Aqua food

OiOI Koi Logo

About Us

A couple of koi nuts! At OiOi Koi we have a passion for all things koi, from hand selecting fish, pond maintenance and pond design, we are proud to offer our expertise to Essex, Suffolk and surrounding areas.

Our Story

OiOi Koi is owned by Barry and Kate Jeffery who have 10 years of experience in Koi keeping and growing. Barry’s interest in koi started at a very young age as he grew up helping his dad with pond builds and landscaping. His interest in koi was ignited when his dad received Custard, a beautiful Yamabuki Ogon from a close family friend and koi dealer.

In 2010 Barry and Kate built their first pond and that reignited that passion for koi.

To crystalize their knowledge and experience gained over the years, Barry has recently become fully qualified in water filtration, fish biology, fish health, pond construction and water quality, and is currently studying a higher level certificate with Koi Organisation International.

Our aim together is to be able to offer good value to all of our clients, with honest and knowledgeable advice – pond enthusiast to pond enthusiast, koi keeper, to koi keeper.

We want to make pond and koi keeping simple, so others can enjoy the amazing benefits having a pond in your life can bring.

Who are we?


Key skill: The Mastermind and pond visionary – as the resident water quality and filtration expert he knows how to keep a healthy pond. Anything from unhappy fish to working out the best pond system for your situation and budget, its alway worth a yarn about your pond goals. 

Favourite fish: Goshiki

Inspiration: A fish called Custard

Experience: 10+ years pond and koi keeping. Landscaping and garden design.


  • City & Guilds Accredited – OATA Foundation Training Programme:
    • Water Quality
    • Filtration
    • Fish Biology
    • Fish Health
  • K.O.I Organisation International:
    • Water Quality
    • Pond Construction


Key skills: Great eye for a good looking fish, maintenance queen – nimble – perfect for awkward situations – leak specialist!

Favourite fish: So many…current swoon is a Karashigoi, or a blue eyed sanke, perhaps a beni kumonryu..did you say one fish?

Inspiration: Dads pond and the evolution of – curses the chemist for losing the picture of the day it was filled.

Experience: 10+ years koi and pond keeping

Qualifications: Working towards City & Guilds Accredited OATA Foundation Training Programme.