How to Choose Aquaponics Grow Bed Material

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One of the major differences between aquaponics and traditional gardening is the utilization of grow bed material. 

In traditional gardening, the soil is used. However, when it comes to aquaponics, there are several types of grow bed material that can be used.

Therefore, choosing the appropriate grow bed material is critical to planning your aquaponics setup. 

There are several factors that you need to consider when choosing your aquaponics grow bed material. First, it should be pH neutral. Second, it should be safe for you to touch. Third, it shouldn’t be too light or too heavy. Fourth, it should not cost you a lot of money. 

If you’re new to the world of aquaponics, you must understand what grow bed material is, factors to consider when choosing that material, and some of the most commonly used grow bed material.

We will explore each of these areas below. 

What is Aquaponics Grow Bed Material? 

As we briefly mentioned, aquaponics involves growing plants without soil. 

Instead, natural or synthetic materials are used to support the crops.

This ensures that the roots are anchored properly, and seeds are able to germinate safely within the material instead of in the ground. 

What is Aquaponics Grow Bed Material?
Aquaponics grow bed material

The grow bed material helps plants soak in nutrients and keeps them from falling over during inclement weather.

Additionally, they provide an area for vital bacteria to grow. The grow bed material is a critical part of the foundation of this form of gardening.

This means that before you start planning your system, give yourself time to learn more about your options. 

However, you should also be aware that not all methods of aquaponics require grow bed material.  

Things to Consider When Selecting Grow Bed Material 

There are lots of grow bed material options on the market, and while many prefer non-organic materials, there are some that prefer to use organic. 

Now that you have an understanding of what grow bed material does, let’s take a closer look at things you should consider when making your selection. 

pH Neutral 

One of the steps on the maintenance checklist for an aquaponics system is to make sure that you keep an eye on the pH level. 

When choosing grow bed material, keep in mind that some materials can have an effect on the pH level. This can potentially hurt your fish and delay plant development.

If your grow bed material is pH neutral, it will be easier to manage the pH level of the system. 

Safe to Touch 

Touching the grow bed material
Safe to Touch

Since you will be touching the grow bed material, it’s critical that you make sure it’s safe to touch.

Plus, ensure that it’s easy to work with and won’t cause any injuries to your hands. 


The weight of the grow bed material is important, especially if you have a smaller or flimsy setup. 

When choosing your grow bed material, you must make sure that it’s not too bulky/heavy, or you may have trouble managing it.

Plus, if it’s too heavy, it could end up damaging the garden bed. 

Since a larger setup is typically going to be much heavier already, choose a material that is light to medium weight.

When you spread it, make sure you spread the weight evenly across the bed. 

Finally: Depending upon whether the material is coarse or fine, it could cause issues by clogging the pipes in the system. 


Cost is definitely a factor that should be taken into consideration, especially if you’re just getting started. 

Some of the materials are going to be more budget-friendly, and others will be more expensive. Consider your budget and try to stay within that.

Of course, you should also keep in mind that some materials can be reused, so though it may cost more upfront, it will ultimately pay for itself since you won’t need to replace it as often. 

Grow Bed Material Options 

Grow bed material options
Grow bed materials

Now that you know what you should consider when choosing your grow bed material, let’s take a look at some of the options. 

Keep in mind that while these are considered the best ones, each of them has its own advantages and disadvantages.

Remember This: No grow bed material is completely perfect. 

Lava Rock 

Lava rock is what is formed when hot lava cools rapidly.

If you want your grow bed material to have lots of surface area, this is a great choice. 

There are air pockets inside these rocks, which provide additional surface area for bacteria to grow. Plus, they are pH neutral, lightweight, and provide good drainage. 

However, they do have sharp edges that can cut your hands or harm the root system of your plants.

If you do choose lava rocks, they should be soaked for a few days to prepare them for cleaning. 

Clay Pebbles 

Like lava rocks, clay pebbles offer plenty of surface area and are pH neutral. 

While this grow bed material is only appropriate for certain plants, there are many on that list.

Clay pebbles have tiny holes that allow them to hold adequate water while allowing sufficient drainage and providing good airflow.

While clay pebbles are a great option for grow bed material, they are not the most budget-friendly option.

Additionally, they tend to float during the first use, which can impede your system.

Expanded Shale 

Expanded Shale
Expanded shale

Expanded shale is similar to lava rock in that it contains air pockets which provide additional surface area for bacteria to grow. 

It’s created from the crushing and heating of silicon-based shale.

This material is pH neutral, and the edges are polished, which means they’re easier to handle and are not likely to damage plant roots.

One of the benefits of using this material is that it’s reusable and typically more budget-friendly than other options.

However, while it’s lightweight and porous, it tends to be heavier than clay pebbles.  

Final Thoughts 

In recent years, aquaponics has become a popular way to grow fresh fruits and vegetables.

This method uses materials other than soil in the grow bed. 

However, there are so many options, and it’s hard to know which one to choose.

If you’re just getting started, you should consider the pH level of the material, whether it’s safe to touch/work with, the weight, and how much of an investment it will be.

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