An Introduction To Aquaponics: The New Approach To Gardening

You may have heard of aquaponics, the amalgamation of aquaculture and hydroponics. Of course, the idea of keeping fish in order to grow plants without soil does sound more complicated than traditional gardening methods.


However, it’s actually very easy to set up, and you’ll be pleasantly surprised by how little maintenance is required.

In fact, plants will grow much faster in an aquaponics system compared to traditional gardening methods.

Let’s take a look at the basic elements involved in establishing your system and how it works.

The Basic Aquaponic System

There are mentions of aquaponic systems dating back to the Aztecs and Mayans when canals and floating rafts were used to grow crops. The same basic principles apply today but in the comfort of your own garden.

An aquaponic system requires fish, which are kept in a tank or even an outside pond. It also requires a container where the plants will grow. The tank and the container are connected with water pipes and a pump is used to transfer the water from the fish tank to the grow bed.

Once you have the system established you will only need to feed the fish and test the water quality.

The fish produce waste, this is in the form of ammonia. In a normal fish tank, the water must be filtered to remove this ammonia as it is toxic to the fish.

However, in an aquaponics system, the water is pumped to the grow beds. Here, bacteria which form on the grow media will convert the ammonia into nitrites, and then into nitrates.

Nitrates are food for plants. They absorb these through the grow media and effectively clean the water; which is then returned to the fish tank.

The fish have a high-quality environment in which to flourish, as do the plants.

The great thing about this system is that you can start small, with just a few fish and a small grow bed. Then, once you appreciate how effective and enjoyable this approach to gardening is, you can scale up the size of your system.

The grow beds can be used to grow plants or food; the choice is entirely yours.

Location, Location, Location!

In property, the location makes a huge difference to the desirability of the home. With aquaponics, the location can be anywhere!

You can set a small aquaponic system up above your existing fish tank in your home. Or, you can go large scale and create a pond in your garden attached to huge grow beds.

The only real consideration is what your climate is like and what climate the plants you want to grow need. If you live in a cooler climate and want to grow warm weather plants, you may need to invest in a greenhouse.

Choosing the Right Fish

The most commonly used fish in aquaponics is tilapia. But, there are plenty of other varieties that will do just as well; such as perch, arctic char, catfish, Koi carp, or even goldfish.

There are two elements to consider when choosing the fish for your tank:

1. Hardiness

If you’re growing warm weather plants then you’ll need to maintain the temperature of the air and the water for your plants. This means you need fish that are comfortable living in warmer waters.

The hardier the fish the easier it will be to look after them when temperatures, and even pH, or ammonia levels fluctuate.

That’s why tilapia tend to be so popular. They are adaptable to most temperatures and can accommodate a wide pH range.

Of course, the fish don’t have to be hardy if their temperature and pH needs are matched by the needs of your plants; and you are confident you can maintain the right parameters.

2. Taste

If you’re considering growing the fish to plate size, then you need to choose a fish that you will actually enjoy eating.

However, you must be aware that removing fish to eat them requires you to either breed the fish or add fingerlings; in order to preserve the ammonia production levels for your plants.

Understanding Grow Beds

The standard rule in aquaponics is that a 1lb fish will need between 5 and 10 gallons of water. Each cubic foot of grow bed will need approximately 6-8 gallons of water.

So, if you want 10 cubic feet of grow beds you’ll need between 60 and 80 gallons of water; and between 6 and 16 1lb fish in your tank. The exact number will depend on the size they are when fully grown

Having chosen your fish, the size of your beds and the associated tank size; you’ll need to choose a growing media.

This is what you’ll fill your container with instead of soil. Your plants will grow in this media and their roots will get all the nutrients from the water being pumped through the grow beds from the fish tank.

There are two ways in which the water can be put through the grow beds:

1. Continuous

Water is pumped from the fish tank and into the growing media at a steady pace. It filters through the grow media and then back to the fish tank. Unsurprisingly, this water flow is continuous.

2. Flood & Drain

The alternative is to pump at least a third of the water from the fish tank into the grow beds in the space of 15 minutes. This is then allowed to drain back into the fish tank, ideally via a bell siphon and then the process is repeated.

This is actually the simplest system to establish and gives the bacteria the time they need to convert the ammonia into nitrates and feed the plants.

You will need to choose which type of growing media best suits your purposes:



There is no doubt this is the cheapest option but it can contain limestone which will affect the pH of your water. You’ll need to wash and check it thoroughly before you use it.


River Rock

River rock is also likely to contain limestone and will need to be washed thoroughly before being used. It is generally smooth which means it will be kind to your hands.

However, it should be noted that it is also heavy; you’ll have to build your media bed with this in mind.


Clay Pebbles

These are extremely lightweight but supportive enough for plant roots. They are pH neutral and highly porous; helping them to retain water and oxygen for the plants.

It should be noted that these are smooth, making them easy to work with; but they are not the cheapest option.


Lava Rock

These are also great at retaining water and oxygen. They also provide great drainage and can even boost the nutrient content of the water.

But, they are generally jagged and will need to be handled with care if you like your fingers in one piece!

Extra Thoughts Concerning Growing Media Types

The above media are all suitable for a standard grow bed. This operates in much the same way as a soil bed. However, there are several other options when creating an aquaponic system:

1. Floating Rafts

Instead of using growing media you can create canals where the water flows from the fish, though the canal and back to the tank. The plants are then placed on trays which allow their roots to have access to the water below. These trays are then allowed to float on the water, giving your plants everything they need to flourish.

2. NFT: Nutrient Film Technique

A similar, but slightly different approach, is to have pipes where the water trickles through continuously. The plants are placed in cups and then into holes created in the pipe. This allows them access to the water and essential nutrients.

However, this type of system is not a good option if you want to grow leafy vegetables or anything with a large root base; they’ll block the pipes.

Benefits Of Aquaponics

There are a number of benefits associated with aquaponics that show why this new approach to gardening should be experienced by everyone.

1. Disease

Diseases in the soil and carried by pests are virtually eliminated in an aquaponics system. This is because the system is elevated and inaccessible to the majority of the pests that can cause an issue to your plants.

2. Produce

The growth rate of plants in an aquaponics system can be twice as fast as the traditional, soil-based, approach to gardening.

Alongside this, by controlling the temperature for your plants and fish you’ll be able to grow plants throughout the year; even when they wouldn’t normally grow.

This is great if you love a particular vegetable and can only normally get it once a year!

3. Ease of maintenance

You’ll need to check the pH, temperature and nutrient levels of your water every day. A visual inspection of your plants is also a good idea. However, that’s it. There is no need to weed your grow beds, add fertilizers, or insecticides.

In short, there is very little that you need to do in order to grow your produce!

4. Inside or outside

Aquaponics systems can be established inside your house, in your greenhouse, or simply in your garden. They are versatile and can be expanded as you feel the need.

5. Environmental Issues

Taking the aquaponic approach to gardening means you’ll be using less water than if using traditional gardening. The fact that the system is self-contained means that you never need to add water, power usage is minimal and no damage to the environment occurs.

6. Organic

There is no better way of knowing where your food comes from than to produce it yourself! This is the ultimate organic food and you’ll feel incredibly satisfied when you take the first bite of your own produce.

Final Thoughts

Aquaponics is for everyone! You don’t need much space to get started, but, once you do you’ll be smitten. It’s an incredibly simple, low maintenance way to produce your own food or plants for decoration.

That’s why, if you haven’t tried this new approach to gardening already; it’s time you did.

About the Author Laura Bennett

Hello, I’m Laura Bennett. I love nature especially when it comes to flowers and different kinds of plants. I started a very small garden behind my house and I named it Humid Garden. So, I created this blog to provide aspiring and inspiring thoughts about gardening for gardeners and anyone who has the intention of keeping a garden.

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