Trying something new is thrilling, especially when aquaponics offers a wonderful chance to become a prosperous gardener and provide your family with organic produce.
When it comes to aquaponics systems, there is a lot to learn in order to have a low-maintenance system. While selecting a grow bed and tank is easy, the various options for aquaponics grow media can be overwhelming.
What is Grow Media?
It is important to first grasp the purpose of the growing media. It should be noted that not all systems utilize grow media before proceeding. One instance is the floating raft system, where plants are situated on rafts with their roots hanging in the water.
However, understanding the effectiveness of aquaponics grow media will make you realize the significance of having it in your system.
- A substance to keep roots in
For a plant to grow and become properly established, a strong root structure is required. This enables the plant to absorb the necessary nutrients and also ensures its stability. In the natural environment, robust roots offer support against toppling or displacement during adverse weather conditions.
Even though your aquaponics system is shielded from the elements, the plant still needs strong roots in order to grow and bear its own weight.
The function of the aquaponics grow bed material is similar to soil, as it offers the plant stability and access to nutrients. Grow media is ideal for plants that require a robust root system. Experiment by cultivating a papaya tree in a DWC or NFT system!
- Surface area for bacteria
To maintain an aquaponics system, bacteria are necessary to convert fish waste (ammonia) into nitrites and then nitrates, which serve as nutrition for the plants.
For this process to happen, the nitrifying bacteria require a surface to adhere to. In flood and drain systems, this surface is provided by the growing media. The ammonia conversion rate improves as the surface area (BSA) increases, allowing a higher number of bacteria to thrive.
By using small grow media or larger quantities of bigger grow media, you can attain a significant surface area. Hence, it is important to understand the various types and determine which would be most suitable for your system.
Requirements for Grow Media
Before choosing the best option, it is important to consider a few things when selecting your aquaponics grow media. Essentially, almost anything can be utilized for this purpose.
Gentle on the hands.
When it comes to the grow media, specifically placing it in the grow bed, you will need to take care of it. This implies that you need something that is comfortable to handle and that you are willing to work with. For instance, lava rocks have pores and a significant surface area. However, they are also sharp and capable of causing cuts on your hands.
Affordable prices are a key factor to consider.
When considering the cost, it is important to think about the type of aquaponics grow media you want to use as it can differ significantly. Hydroton is an example that is especially expensive, whereas gravel is usually the least expensive option. If you are a beginner, it is crucial to find a balance between your budget and the expected outcomes.
Maintaining the same meaning, rephrase the text step by step. Do not add or remove information. “Ph neutral.”
Controlling the pH level in your system is crucial and requires daily attention. Both your fish and plants have their own preferred pH range, so it is ideal to select ones with a similar range (a pH of 7 is suitable for an established system).
When considering grow media, it is important to be mindful that certain types can change the pH of your system. This can potentially hinder plant growth and harm your fish. Therefore, it is advisable to steer clear of limestone as it is commonly utilized to increase pH levels, and it is highly effective in doing so.
It is recommended to test your grow media with vinegar before adding it to your system, as a precautionary measure. The process is straightforward: thoroughly wash the grow media and then submerge it in a container filled with vinegar, ensuring it is completely covered.
If bubbles are observed, it indicates that the pH is high, which is a result of the reaction between vinegar and limestone. The quantity of bubbles corresponds to the amount of limestone present, as more bubbles indicate higher limestone content. Conversely, the absence of bubbles signifies a pH-neutral state, which is desirable as it simplifies pH regulation in your system.
Surface area that is of good quality.
As previously explained, the system’s ability to convert ammonia to nitrates is improved with a larger surface area for bacteria in your media.
When considering the size of your system, it is important to take into account that different types of media will provide varying surface areas that may be more suitable.
Decomposition is the process of breaking down something into smaller parts or simpler components.
To ensure the durability of your chosen aquaponics grow media, it is crucial to confirm that it will not deteriorate or decompose in your system. Any breakdown or decomposition could limit the space available for bacteria and lead to blockages or anaerobic pockets, which can harm your plants significantly.
Different Grow Media
Let’s examine the most commonly chosen aquaponics grow media options:
Rocks that are made of lava
- Lots of surface area
- Hard on the hands
Lava rock is created through the rapid cooling of red-hot lava, which results in the entrapment of air pockets within the rock, greatly enhancing its surface area.
Additionally, these rocks guarantee lightweight and excellent drainage, and they are usually pH-neutral. Nevertheless, their sharp edges can result in cuts when handling them and potentially harm some plant roots.
They are a viable choice, although not necessarily the optimum one.
Hydroton, clay pebbles, or expanded clay can be thought step by step.
- Lots of surface area
- Expensive
Hydroton, an expanded clay product, is an excellent option for growing almost any plant due to its clay composition. Clay, rich in microscopic holes, enables effective drainage and adequate water retention for the optimal well-being of your plants.
By increasing the surface area of this grow media, these tiny holes play a significant role in ensuring an abundance of nitrifying bacteria for your aquaponics system.
In addition, it maintains its shape, promoting a high level of airflow, and surprisingly, it has a pH level that is neutral.
Additionally, being one of the priciest alternatives, it has a tendency to float initially, which has the potential to result in clogs in your pipes and filters.
River rocks are smooth stones that are typically found in riverbeds.
- Cheap
- Readily available
- Heavy
River rock is typically rounded due to the river’s flow shaping it. This option is inexpensive and can be found at local stores. It is recommended to choose a medium grade, as smaller rocks can potentially clog the growbeds. On the other hand, selecting larger rocks will not provide the desired surface area.
If you are new to aquaponics, this media is suitable for you, but keep in mind that it is quite heavy, so ensure that your grow bed can support the weight.
Before using it, you should wash and check the pH of it. It is very likely that it contains limestone, which will raise your pH levels.
Pea gravel, when considering each individual step, should be restated while keeping the meaning intact. No extra information should be added, and no information should be removed. Thus, “Pea gravel” cannot be further restated.
- Lots of surface area
- Might clog up the grow bed faster because it’s small
- The danger of limestone
The lowest priced option is typically pea gravel, although it is necessary to verify the composition of the gravel. It gets its name from the small dimensions of each piece, and it can be crafted from nearly any substance.
Ensure that the material you select, such as quartz or limestone, is thoroughly examined so that you avoid using unsuitable alternatives like pea gravel. It is crucial to test whichever option you opt for to confirm the presence of limestone; if the test indicates a positive result, refrain from utilizing it.
Due to its small size, pea gravel provides a significant bacterial surface area; however, it is important to take preventive measures to avoid the formation of anaerobic zones in your growbed.
Expanded shale is a material that has undergone a process to increase its size.
- Lots of surface area
- Hard on the hands
Firstly, this text states that the mentioned substance is a natural shale that undergoes heating to around 2000°F. During this procedure, the shale expands, resulting in the formation of numerous small air pockets within it. This expansion contributes to the increased porosity of the growing medium and its surface area.
This product is an appealing and feasible option because it is almost as inexpensive as pea gravel. Additionally, the sharp edges are eliminated during the heating process, ensuring that you won’t injure your hands when handling it.
can be used in place of soil in gardening or hydroponic systems. These alternative mediums provide a porous and lightweight material that allows for proper aeration and root growth. They are composed of recycled glass and are environmentally friendly. Additionally, Growstones or hydrostones also retain water well and can be reused multiple times. They are a suitable option for gardeners looking for sustainable and efficient growing mediums.
The last item on this inventory is known as grow stones, which are recycled glass products that are lightweight and porous. To make sure they are pH-neutral, they undergo a preparation process. Additionally, the creation process ensures that they have an ample amount of pores for nitrifying bacteria.
- Lots of surface area
- Ph neutral
- Not readily available
- Rough on the hands
However, it is crucial to mention that their surface is comparable to sandpaper. Therefore, caution must be exercised while handling them and ensuring that your fish are compatible with this particular type of media.
Which Grow Media Doesn’t Work?
With the exception of a few, majority of media options are effective in an aquaponics system.
Rephrased: The text requires step-by-step thinking in order to maintain its original meaning. Do not introduce new information or omit any information. Sand.
Sand, being very fine, possesses a substantial surface area for bacteria to thrive. However, it also leads to the obstruction of your growbed, resulting in the formation of anaerobic zones deprived of oxygen, which can be detrimental to the well-being of your beneficial bacteria.
Sand can be used as a grow media in systems known as iAVS or sandponics, but I do not advise it for beginners.
The organic matter must be thought of in a step-by-step manner while ensuring that no new information is added or removed.
While they may initially appear to be a beneficial choice, organic materials such as coconut coir and other degradable items will break down within your system. As a result, pockets of decomposing waste will form, consequently impairing the ability of nitrifying bacteria to perform their duties.
Additionally, the matter in the process of decomposing has the potential to be drawn into your pipes and filters, resulting in damage and obstructing the water flow that your plants rely on.
Selecting Aquaponics Growing Media
In the process of constructing an aquaponics system, there are various options to consider for the growing media. If you happen to have an abundant supply of small pea gravel or river rock in your backyard, you could consider utilizing it. Alternatively, if you plan on using numerous growing tubes instead of large beds, you may prefer something that resembles soil for convenience. However, regardless of the choice you make, the selected growing media must possess good drainage to prevent waterlogging and subsequent root rot.
The majority of individuals opt to use expanded clay pebbles in their aquaponics system. These pebbles, typically measuring 4-16mm, are the preferred size as they provide ample room for the roots to navigate comfortably. Furthermore, they possess a substantial air content and high porosity. Another advantage is their durability, as they do not decompose or deteriorate, making them a long-lasting option. In addition, they are resistant to fungal growth. Additionally, compared to materials like pea gravel, expanded clay pebbles are significantly lighter, decreasing the need for sturdiness in the construction of your grow bed.
Pea gravel or small river rock is a viable choice for an aquaponics system due to its affordability, which is why it is commonly preferred by many individuals. However, it is important to bear in mind its considerable weight during the construction of your grow beds.
Additionally, I have heard individuals mention the utilization of materials like peat moss, coconut coir, rockwool, perlite, and vermiculite. Typically, these materials are packed into small plastic baskets and seeds are then planted in them. This method prevents seeds from inadvertently being washed away or sinking to the bottom of the growing area. It also allows you to initiate seed growth indoors, where you have better control over light and temperature, and subsequently relocate them outdoors when they are suitable for transplantation (similar to conventional garden seedlings). However, if you have an abundance of coconuts in your yard, it is worth considering creating your own filling material for starter pots.
If you have an unlimited amount of any of these materials mentioned earlier, you may choose to use them solely as the grow bed media. Among these options, peat moss and coconut coir are commonly utilized. However, it is important to acknowledge that over time, they will decompose and deplete oxygen from your system. Additionally, peat moss is highly prone to hosting mold and fungi, which is undesirable.
