Aquasoil's Second Life: Reusing Aquasoil
Allen OrtegaEvery aquasoil will run out of nutrients eventually. Being only a couple months to a couple years, the nutrient capacity will deplete. However, this does not mean that the soil is no longer usable. Through many different ways, this soil is still very much useful. Let's go over the different ways we could reuse soil.
Reusing in the Aquarium
It would seem counter-intuitive to reuse aquasoil within one's aquarium, as it no longer has nutrients. However, there are many ways to reuse it within the aquarium. Once the aquasoil is cleaned off (as a lot of plants, such as Rotala Tulunadensis does not like a dirty substrate), it's new life may be started. However, here, we recommend to possibly try and rejuvenate the soil (see the next paragraph). This method works especially well when using new aquasoil under the older aquasoil, as the lower layer will have a lot of nutrients, while the water column will have much less nutrients. This way, it may be much faster to add fish right away (in this tank, fish were added only 1 week after). We had planned to incorporate this idea that was originally brought from Sudipta Shaw when he talked about it in his AGA 2024 convention talk.
Reusing in the Aquarium
It would seem counter-intuitive to reuse aquasoil within one's aquarium, as it no longer has nutrients. However, there are many ways to reuse it within the aquarium. Once the aquasoil is cleaned off (as a lot of plants, such as Rotala Tulunadensis does not like a dirty substrate), it's new life may be started. However, here, we recommend to possibly try and rejuvenate the soil (see the next paragraph). This method works especially well when using new aquasoil under the older aquasoil, as the lower layer will have a lot of nutrients, while the water column will have much less nutrients. This way, it may be much faster to add fish right away (in this tank, fish were added only 1 week after). We had planned to incorporate this idea that was originally brought from Sudipta Shaw when he talked about it in his AGA 2024 convention talk.
New aquasoil, ADA root tabs, and NILOCG root tabs.
After this, one may start to layer the old soil on top of the older aquasoil and may be planted. This is the most cost-effective method when one has a little extra new aquasoil and a lot of old aquasoil, especially when one wants to restart the tank. Following this, every month or so, or after replanting a bush of plants, we could use APT JAZZ root tabs to rejuvenate the surrounding soil and keep the plant / plant roots happy and healthy.
Rejuvenation of Aquasoil
A while back, we found out that ADA actually recommends rejuvenating aquasoil using ADA Brighty Nitrogen. Ammoniacal Nitrogen, found in ADA, APT JAZZ, and NILOCG THRIVE+, is a form of nitrogen more readily available to plants compared to other forms of nitrogen one may use. As ADA Brighty Nitrogen is a 'pure' form (pure meaning the 2 ingredients in the bottle is Nitrogen and water), it is possible to spray the fertilizer on the old soill and let it absorb it. This may temporarily rejuvenate the soil. However, as ADA Brighty Nitrogen also has some water content, it will not be very concentrated. It may be more 'cost-effective' in the matter to instead buy concentrated ammoniacal nitrogen and use directly on the soil (we may experiment on this later on). An easier form of partial rejuvenation (local - not general rejuvenation) is using root tabs with ammoniacal nitrogen, such as APT JAZZ. These root tabs release nutrients which will be absorbed into the soil, as well as the roots of the plants. Therefore, these allow for your plants to grow, and at the same time, to have your soil be partially rejuvenated.
Note: Although this does talk about rejuvenation, it is currently not possible to fully rejuvenate aquasoil as rejuvenation in any method will not bring back the aquasoil to how it was originally, as penetration will not be at 100%.
About 1 month after using old ADA soil on top of new soil, along with ADA root tabs between the old and new soil. Thus, this is a mixture of both the idea of reusing old soil and rejuvenation.
Planting sensitive plants, Germination, and Other Plants
Aquasoil is great for plants, including plants that prefer softer pH, need better aeration, and/or draining. All these benefits are derived from using aquasoil within one's potting mixture. Since aquasoil has a great structure, this would be likely to greatly promote root aeration. This structure is very durable. Depending on which aquasoil one chooses will depend on how fast they degrade, but all the high quality likely ones likely will keep their structure submerged in aquarium for years! Root aeration is very important for roots as it helps develop healthy roots, such as prevent root rot as well as allowing for better absorption of nutrients and water. Sensitive plants (especially ones more prone to issues in roots) will greatly benefit from using aquasoil.
Aquasoil is known for its ability to lower and stabilize pH levels in aquarium settings. When reused for terrestrial plants, this property remains beneficial. Many sensitive plants thrive in slightly acidic to neutral pH levels, and aquasoil, after its initial use, tends to have a stabilized, lower pH. This can be especially advantageous for plants that require specific pH conditions to absorb nutrients effectively. As the aquasoil has already undergone initial leaching in the aquarium, it is less likely to cause drastic pH changes in the soil environment, providing a stable growing medium for plants.
Initially, aquasoils are rich in nutrients, particularly beneficial for aquatic plants. Over time, while some nutrients may be depleted, the soil still retains a significant amount of organic matter and minerals that can benefit terrestrial plants. The nutrient composition of reused aquasoil provides a slow-release source of essential elements such as nitrogen, phosphorus, and potassium. Sensitive plants, which may be more susceptible to nutrient imbalances, can benefit from the steady supply of nutrients without the risk of over-fertilization.
Aquasoil’s composition allows it to retain moisture effectively without becoming waterlogged. This property is beneficial for terrestrial plants as it ensures that the soil remains consistently moist, which is vital for the health of sensitive plants that may require specific moisture levels. The balance of moisture retention and drainage in aquasoil helps in maintaining an optimal growing environment, reducing the need for frequent watering and minimizing the risk of water stress.
After being submerged and used in an aquarium, aquasoil can develop beneficial microbial communities that help in breaking down organic matter and suppressing harmful pathogens. When reused in terrestrial applications, these microbes can contribute to a healthier soil environment by promoting beneficial microbial activity and naturally resisting pests and diseases. This microbial balance is particularly important for sensitive plants that might be more susceptible to soil-borne diseases.
When resusing aquasoil in this case, we would likely recommend mixing it with other substrates, so that the plants do not become too stressed out to completely being in aquasoil. What we personally like, is using a mixture of peat moss (to retain nutrients), sand, and aquasoil. A 2:1:1 (aqusoil:sand:peat moss) works well, but it is up to the gardener to decide which mixture they prefer best!
In certain cases, we have also seen people use aquasoil within bins and lights to transition tissue cultures (of any plant) from the tissue culture to their current (or proposed) environment. Many people have had a lot of success with this.
The 2:1:1 mixture in a bucket.
One may also use this mixture (or 100% aquasoil) for germination of seedlings. For best success, we have found that using pure aquasoil is better for bigger seeds, such as Carolina Reapers (Capsicum Chinense 'Carolina Reaper') or bigger, while smaller seeds, such as for Xyris Pauciflora would germinate better in a mixture, as it would not fall and get lost under the large porous substrate (being 100% aquasoil). As talked with Max Kuntze, a friend that specializes in germination of aquatic seeds, he has also had a lot of success with germination of plants using aquasoil. It seems that using aquasoil (from personal experience), germination rates are much faster. When comparing old aquasoil to potting soil, Carolina Reaper seeds germinated and sprouted after a few weeks in soil, around 4 weeks. However, with aquasoil, germination and sprouting only took a few (about 3-5) days!
Conclusion
Old aquasoil does not need to be disposed of, and should rather be used in many other different places! From helping germinate seeds to continuously helping plants grow, to even having it have some life back, the possibilities with aquasoil are endless! Although aquasoil may seem expensive, for what possibilities it brings, it is 100% worth it. With most aquasoils, their strength relies on how great they perform nutrient-wise. They are packed with nutrients, and their shape and other characteristics allow for this substrate reusable in many places, not just the aquarium. Although we mentioned quite a lot of examples in this article, there are many more out there.
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Conclusion
Old aquasoil does not need to be disposed of, and should rather be used in many other different places! From helping germinate seeds to continuously helping plants grow, to even having it have some life back, the possibilities with aquasoil are endless! Although aquasoil may seem expensive, for what possibilities it brings, it is 100% worth it. With most aquasoils, their strength relies on how great they perform nutrient-wise. They are packed with nutrients, and their shape and other characteristics allow for this substrate reusable in many places, not just the aquarium. Although we mentioned quite a lot of examples in this article, there are many more out there.
Sources