Will my salad taste of fish poo?

For an individual who blagged his way through science at school, this Smart Green faced a week at Kate Humble's place in rural Wales with a certain amount of trepidation.  An intensive week of learning the "alchemy" that is turning fish poo into leafy green crops lay ahead.

I stumbled across the concept of Aquaponics whilst thinking about how to grow our social enterprise.  Faced with the conundrum of how to grow more in the same amount of space, I needed something radical.  Little did I imagine that this would take me on a journey that discounted soil altogether, for Aquaponics is the science of growing plants in water.

My week with Aquaponics UK started by meeting the Class of 2017.  I expected green-fingered fanatics but joined an eclectic band from across the world harbouring a healthy respect for the environment and an interest in growing food, socially and commercially.  With them came a whole series of fascinating scenarios; from growing food in a basement, building edible gardens through to the international challenges posed by working in Vietnam and Kuwait.  Having a couple of acres in rural Oxfordshire began to seem like a home advantage.


However, as the week went on, it become apparent that as long as you can get your head around the theory, how you assemble your aquaponic master-piece is entirely down to you, your preferences and your capabilities.  It doesn't matter whether you want to grow on an industrial scale or to simply feed a family, the numbers (and the science) are what is important.

With the boast that Smart Greens is pitching itself as an ambitious social enterprise ringing in my ears, I needed to find a concept that reflected our ambition.  A Heath Robinson-esque design was out of the question.  We're commercial so need to be taken seriously.  However, we're also not quite ready for a full-on venture capital investment so the middle-ground beckoned.

My first lesson, the numbers are my friends!  I found it a bit like singing the "skeleton-song" where the knee-bone's connected to the shin bone.  Just substitute the names of the bones with the words "fish, plants, seeds and fish food" and everything will become clear.  As clear as the water in a healthy fish tank.  The amount of fish food is dictated by the numbers and ages of the fish.  The amount of fish food dictates the amount of nutrients available to the plants which, in turn, dictates your daily harvest.  Get the gist.  In this way, you can pretty-much design the bones of a scheme using the formula on an Excel spreadsheet, and I love a spreadsheet.

Now, I soon found that the numbers can only take you so far.  In short shrift, I was up to my elbows in fish biology - literally when being taught how to fillet a Tilapia.  My choice of fish is important.  Different species demand different water temperatures and grow at different rates.  Obviously.  If I keep it simple, I can grow goldfish and have lots of pets with cute names like Mango, Tango and Fandango.  If I want to sell my fish to restaurants I have an important choice to make, as many have cultural references.  Tilapia for a broadly Asian market, Carp are favoured by those from the Eastern Bloc, Perch for Ireland, Trout for the English...


I haven't even mentioned plumbing, water flow, pH, nitrites and nitrates. That is for another time.  For now, I want you to concentrate on fish and leafy greens.  Leafy greens that grow quickly with an intense flavour, allowing for grow-to-order and close working relationships with foodies, chefs and independent food businesses.

Needless to say, Aquaponics is not for the faint-hearted.  I used to run towns and cities in a previous life so was routinely a marketeer, policeman, event planner, business advisor, retailer, politician and more as the job demanded.  It would seem that I have swapped these to become biologist, plumber, fisherman, fishmonger, farmer and forensic accountant.

What an amazing week!