How Deep Should an Aquaponics Grow Bed Be?

How Deep Should an Aquaponics grow bed Be? - Green Garden Tribe

Have you ever heard of Aquaponics? If not, this article is for you since we will talk about the process of Aquaponics, how deep it should be, how to create Aquaponics and several Aquaponics designs.

The idea of Aquaponics is not complicated as compared to its name. Everyone can create Aquaponics with the right equipment and details and know how to do it properly.

What is Aquaponics?

The term aquaponics is a mergence of aquaculture and hydroponics. Aquaculture is the act of domesticating fishes and other aquatic animals. Hydroponics is the process of growing plants without using any soil.

In a nutshell, Aquaponics is the process of putting fishes and plants together. It’s not like you throw plants in an aquarium, but more fashionably and healthily that both plants and fishes benefit from one another. In other words, Aquaponics is another method of farming aiming to provide better nutrition for fishes and plants.

Moreover, Aquaponics is also considered an agricultural strategy by raising both fish and plants. This process is deemed sustainable and is widely practiced among individuals with a passion for agriculture, entrepreneurs, and even governmental agencies.

How Deep Should an Aquaponics Grow Bed Be?

The desired growth bed depth of every Aquaponics depends mainly on the type of plants you want to nurture in the aquaponics system and your financial capacity.

Take note that the recommended media bed depth is 12 inches long. Also, there are three different types of zones in a grow bed: dry zone, root zone, and mineralization zone.

The dry zone or the surface zone covers the first five inches of the grow bed. This area should be kept dry since it helps to prevent evaporation. This area also discourages the growth of algae and other moisture-related diseases, which could post severe damage to the Aquaponics.

The root zone is located around six to eight inches deep in the grow bed. This area is regularly flooded and drained with a cycle starting from the spread of nutrients and fish waste with water in the area. Worms are also placed in this zone to break solid waste formation by eating dead leaves and roots.

The mineralization zone is located at the remaining two-inch bottom part of the grow bed. This is where most of the fish waste and worm castings are formed. Heterotrophic bacteriaOpens in a new tab. and other friendly microorganisms are used to break down waste particles into smaller molecules enough to be absorbed by the plants.

Now, since we already understand the different zones of grow beds, another factor to consider when deciding the grow bed’s depth is the type of plants and budget availability.

Shallow grow beds will have limited plants to grow in the aquaponics system. Hence, knowing the type of plants you want to put in the aquaponics system and your budget is necessary to determine the grow bed’s precise depth.

You should ask yourself whether you will grow purely leafy greens or other types of crops and whether you can finance the whole project. Your answer will fix the problem regarding the Aquaponics grow bed depth. Always remember that getting the right depth of grow bed is essential to the aquaponics system’s success.

To give you a balanced perspective, we will differentiate between shallow and deep Aquaponics grow beds. Although most experts agree that the recommended media bed depth is 12 inches, it is enough to keep the aquaponics system working. Anything more than this measure is unnecessary and a waste of resources, especially if you are on a tight budget.

One factor of a deep grow bed is more expensive than a shallow Aquaponics grow bed. This is because you need to put more media, and you also have to create a device that can withstand the weight of a deep Aquaponics grow bed. The amount of water to irrigate at such depth is also included in the calculations.

On the other hand, the shallow grows bed may be proven less expensive and is widely practiced by some people and succeed on it, but still, there are limitations to it. A shallow grow bed means limited options for the plant to grow because it is only designed for plants with non-invasive roots. Generally, the shallow grow bed is for short-lived plants like lettuce and other leafy greens.

In short, if you are planning to go either shallow or deep grow bed, it is also essential to be familiar with different plants that have different nurturing needs. A shallow Aquaponics grow bed is best for lettuce, broccoli, cabbage, and herbs. While the deep grow bed is best for strawberries or tomatoes.

How does Aquaponics Work?

Aquaponics works through combining soilless plants into a big tank where the domesticated fishes are located. Take note that the plants are placed in a customized device to prevent the plants from submerging their entire parts.

The part of the plants submerged in the water will ingest the nutrient-filled water because of fish stool, which acts as a natural fertilizer.

The water will then be purified, making it healthier for the well-being of fishes. This circular process keeps both plants and fishes turn out to be fresh and well nurtured.

The primary purpose of Aquaponics is to simply offer farmers more options to do farming.

Aquaponics is an excellent example of an indoor market that can last up to a year. So, you will reap not just plants but also a hefty amount of fish during harvest season.

Although another purpose of Aquaponics is utilizing the fishes to grow plants by merely “extracting” all the nutrients in the water.

This has proven to be more efficient and effective than the traditional way of growing plants and raising fishes. With this, more families will be able to gather enough food and generate income by selling them.

5 Benefits of Aquaponics

1. Less expensive– Aquaponics does not need any chemical fertilizers, pesticides, and herbicides. Although you may spend on making its setup, it is nevertheless cheaper compared to fertilizer maintenance.

2. Indoor farming- one great benefit of Aquaponics is it can be done anywhere, outdoor and indoor. Most people prefer indoors hence safe from any natural calamities.

3. Healthy Plants– since the plants are free from chemical fertilizers, pesticides, and herbicides, more people will be confident in eating such locally-produced plants, especially the conservative eaters.

4. Fishes and more fishes– always remember that Aquaponics is a combination of nurturing plants and fishes. Hence, you will not just harvest safe and healthy plants, but large and healthy fishes as well!

5. Less labor- the aquaponics setup is made not to drain the strength of the farmers. The least you could do is to observe if anything is wrong such as the infestation of bugs, but this barely happens in an indoor setting. You might want to check on the fishes as well and how they gain size for months.

These are just a few examples of the unlimited benefits that Aquaponics can give to all of us.

How to Take Care of Aquaponics Systems

There are 7 cardinal rules when doing Aquaponics, and they should be followed for easy and successful Aquaponics. Here are the 7 cardinal rules to follow:

1. Pick the best tank

Fish tanks are a crucial part of an aquaponics system; hence it must be reliable and gets the job done. You should pick a tank that has flat or conical bottoms as they are easier to clean. Always pick strong, inert plastic or fiberglass tanks to ensure durability.

2. Enough air and water circulation

You should maintain adequate air and water circulation in an aquaponics system to ensure that the oxygen is properly dissolved in the water, and water movement is good for the fish, plants, and bacteria. Take note that it will indeed use electricity, which needs to be considered for budgeting purposes, thus choose water pumps and power source supply wisely.

3. Keep the water in good quality.

Of course, the aquaponics system cannot work without water since it is where all the nutrients are transported throughout the system. To put it simply, water is the lifeline of every aquaponics system, and it is necessary to keep a good quality of water. The five key water quality measures such as dissolved oxygen (5mg/liter), pH(6-7), temperature (18-30°C), total nitrogen, and water alkalinity shall be observed as well.

4. Limit the number of fishes in the tank

Overcrowding the tank also means there is little space for the fish and the plants to grow. The recommended stocking density is 20 kg/1,000 liters. You can go beyond the recommended stocking density as it can produce more food yet requires more attention.

5. Do not overfeed

Remember that the waste food will root inside the system and can potentially damage the aquaponics system. Feed the animals every day and remove the uneaten food after 30 minutes. On the following day, adjust the amount of food to minimize waste and save a little money.

6.  Space the plants wisely.

Similar to fishes, do not put too many plants in one aquaponics system. Also, short-lived plants and longer-term plants are different. In general, they work well in an aquaponics system if you follow all the seven cardinal rules.

7. Balance the animals and plants

Again, avoid overcrowding plants and animals. Maintaining a good balance of fish and water will keep a steady harvest of fishes and vegetables. You will have a consistent production level every year with healthy fishes and plants.

What are the types of Aquaponics?

Usually, there are three types of aquaponics systems: Nutrient Film Technique (NFT), Media Bed, and Deep Water Culture (DWC).

Each design has its unique advantages and disadvantages. It is also essential to understand their differences for successful Aquaponics.

Nutrient Film Technique (NFT) is popular among commercial industries. This method is proven to be effective on short-lived plants like leafy greens. The plant roots are also exposed to more air and less water, which may result in extreme heat or cold fluctuations experienced by the plants.


Lower labor cost
Space efficient

Nonstop supply of water, oxygen, and nutrients.


Not suited for large fruiting plants
Higher tendencies of clogging
Water temperature fluctuations

Media Bed is another aquaponics design that uses gravel or hydroton to support the roots of the plants. The bed is flooded and drained with water enriched with nutrients to supply the plants oxygen and nutrients.

This design is for beginners or backyard gardeners because it does not need any engineering talent or science background for it to function. It is inexpensive and productive, although on a small scale.

It can also produce large root plants like fruits, vegetables, and root vegetables; however, it is not space-efficient.


Grow large crops
Simple and inexpensive setup
Applicable for small scale gardeners

Cannot elevate into commercial scale
More cleaning is required.
High maintenance and labor
Space inefficient

Deep Water Culture (DWC)

It is sometimes known as “raft or float systems” because it uses floating rafts to suspend plant roots into aerated and nutrient-filled water.

Filtration devices must be built into the design because there are no media that process the solid wastes. As a result, this requires more advanced aquaponics techniques and equipment, leading to the high demand of costs.

This design is popular among commercial production because of its higher water volume feature.

This will allow more nutrients in the system, and temperature fluctuations are less expected to happen. However, this design is best suited in warmer climate places because it is costly to warm the water in cold places given the high water volume.


Commercial production level
Highly productive
Inexpensive (compared to Media Bed)
Not susceptible to temperature fluctuations


Filtration demands
Labor demands
Space inefficient
Not suited for warmer climate places

These three significant designs are the most common designs when building an aquaponics system. Now that we are familiar with each design’s differences, the next step is to pick which designs suit you putting into account the financial capacity and location.

Patricia Godwin

Patricia has many years of experience as a content writer on various subjects, but her first love is gardening. She’s never met a plant she didn’t like and, consequently, she writes about every type of plant you can think of. Once an avid gardener with a herb garden, a succulent rockery, and a rose garden – to mention a few. Nowadays, she’s constantly on the move searching for interesting plants to bring to your attention; and explain to you all the details you need to grow, care and maintain these plants.

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