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The Most Compelling Reason

Typical daily harvest from my home Aquaponics system.

Food Purity

Food purity is one of the main reasons a lot of people get into aquaponics. Every time I run my 4-Day Aquaponics MasterClass, I ask students what their interest is in learning about aquaponics. And without fail, Food Purity is always one of the main reasons.

People are concerned about the grubby stuff that’s going into their food, these days! Pesticides and herbicides and preservatives and artificial colours. Even if the first dose won’t kill you, over time it can build up in your body and cause a whole lot of health issues.


Take mercury in fish, for instance. Mercury is a natural substance, but through various processes – some of them natural, some of them industrial – it gets converted to a toxic chemical called methylmercury. This is really easily absorbed into living cells and it never goes away. Once you have it in your system, it’s there for life. It’s what’s called a ‘persistent’ toxin.

Not only is it persistent, but it ‘bioaccumulates’ or ‘biomagnifies’ as you go up the food-chain. That means that an animal higher up the food chain will contain more mercury than animals lower down the food chain because it now contains all the mercury from all the animals that it ate. For example, let’s say there’s a group of small fish in the ocean, each containing a small amount of mercury. If you eat one of those fish, you ingest a small amount of mercury. Now, let’s say a larger fish comes along and eats all of those smaller fish. All of the mercury in their bodies now takes up residence in its body. And then you eat it! So, what do you get? All the mercury from all the smaller fish! That’s what bioaccumulation means. The toxin builds up in the food-chain until eventually, you eat it at a dangerously high level.

Food Additives

But it’s not only major toxins like mercury that people are worried about when it comes to food purity. Food additives are also a concern for a lot of people. Pick up just about any pre-packed food and read the ingredients. It’s like a mad scientist’s shopping list! Benzo this and butyl that, and a whole lot of numbers that only a chemist would recognise. At low levels, most of them are considered fairly safe, but so many people these days are eating so much packaged food that it is becoming a problem. Allergies and sensitivities abound.

Now, while we’ve come to expect additives in pre-packaged foods, it’s a real concern to know that you can find nasty chemicals even on fresh fruit and vegetables! Producers cover them in a whole range of things to extend their shelf life or make harvesting and transporting easier. Unfortunately, this often means that you, the consumer, end up with flavourless, nutrient-poor food. In some cases, you’re better off buying frozen or canned – the ‘fresh’ produce may have been picked months ago, while the canned or frozen stuff was probably still in the ground the day before it was packed.

Nutrient Poor Food

Even the types of crops that are grown these days are chosen for their packageability rather than their nutritional value or flavour. And a lot of them are picked unripe before they’ve had time to develop their true flavour and full nutrient content. Again, this means we end up with lower-nutrient, lower-flavour food. This is why a lot of people are starting to grow their own – they can choose from a wider variety of crops and they can let them ripen properly before picking them. This means they end up with food that is flavoursome and nutrient dense. And I can tell you, there is just no comparison between biting into a soft, sweet, juicy strawberry that you’ve just picked from your own garden, and the bland, crisp, woody ones you so often find in the supermarket these days.

Genetically Modified Food

Another aspect of food purity that’s become an issue for many people is the use of genetically modified (GM) foods. This is a real hot button for some people. Like any argument, there are two sides, with some people saying GM food is the only way to feed the world, while others say it’s going to kill us all. But it is a major reason some people are starting to grow their own food.

Grow Your Own – Aquaponically!

Growing your own food is absolutely the best way to know that it’s going to be clean, fresh and nutrient rich. Farmers’ markets and buying organic are great and may be the only thing you can do if you don’t have the time or space to garden. But if you really want to make sure you know exactly what’s gone into your food, there is no substitute for growing it yourself.

And this is what attracts a lot of people to aquaponics. It’s a clean-food machine! You can’t add any nasties to it or you’ll kill your fish and the microbes that make the system run. So, because you have to take care of your system like that, it will take care of you by providing you with flavourful, nutrient-dense food, right in your own backyard. No more rubbery cucumbers or rock-hard tomatoes. Just fresh, clean food the way it was always meant to be. How good is that!

[references for the mercury, food-additives and GMO section]

Mercury exposure and poisoning

Mercury in the food chain

Fesh Food Tricks

Food Additives to Avoid

Genetically Modified Food FAQ

Posted By Murray Hallam on 30th December 2017

Updated : 27th May 2020 | Words : 924 | Views : 63426

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