What is Vermicompost?
Vermicompost is the end product of vermicomposting, a process that uses earthworms (red worms in aquaponics) to increase the speed of the composting process. The chemical secretions in the worms’ digestive tract help break down the soil and other organic matter, so the worm castings contain more nutrients that are available to the plants. (1)
Vermicompost contains water-soluble nutrients and is an excellent, nutrient-rich organic fertilizer that is used for farming and small scale sustainable organic farming like aquaponics. Vermicompost helps to enhance plant growth, crop yield and help improve the root structure and development of the plants. Vermicompost can be made into a liquid form by making it a vermicompost tea.
What is Vermicompost Tea?
Vermicompost tea is a liquid produced by extracting organic matter and nutrients from vermicompost. Vermicompost tea is an easy way of providing nutrition to your plants. By steeping or brewing your vermicompost in water, the nutrients and beneficial microbes are easily absorbed by the plants. (3)
Vermicompost tea can be made by filling a cloth such a pillowcase or material bag with vermicompost and tying the opening. Place it in the water and leave to steep with an air pump oxygenating the water for a day or two. The brown water will be your vermicompost tea. (3)
Using Vermicompost in Aquaponics
One of the goals of aquaponics is to create a sustainable and organic farming practice. To achieve this goal, an aquaponics system needs nutrient-rich water to promote the optimum growth of the plants.
One question in aquaponics is if the nutrients from the fish waste are enough to supply your growing plants with all the mineral elements that they require to grow healthy.
As long as quality feed is being supplied to the fish, their waste will possess most of the necessary nutrients needed for the plants to thrive. However, there are still some micronutrients that do not exist in feeds that lead to nutrient deficiencies in your plants like iron, calcium, and potassium.
To deal with these deficiencies organically, vermicompost or vermicompost tea can be used to add nutrients to your aquaponics system. The media-based, ebb and flow or flood and drain system of aquaponics is usually the type of aquaponics system that uses vermicomposting.
The media-based cycle within the grow bed provides an excellent environment in which its high and low water cycle ensures that the beds remain damp and well oxygenated. Worms require oxygen to prevent them from drowning and the damp grow beds make the worms thrive, grow and multiply in this type of system.
The Benefits of Using Worms in Media-Based Aquaponics
- Worms break down the solid waste from the fish, excess roots and other materials that plants cast off and make them available to the plants through their feces (vermicompost). (2)
- Worms feed on small decomposing organic particles, breaking down dead roots and other material thus preventing them from clogging the beds.
- Vermicompost enhances plant growth and aid germination for a higher yield. (3)
- Worms produce antibiotics which helps to protect the plants against diseases. (3)
- Aids in cleaning the grow bed.
- Vermicompost and vermicompost tea aids the aquaponics system in the following pest and disease issues:
- Prevents plant diseases
- Prevents parasitic nematodes
- Prevents insects and pests such as aphids, spider mites, mealybugs and tomato hornworms. (2)
How to Introduce Worms Into Your Grow Bed
Here are some tips in adding worms to your aquaponics system; In buying worms or harvesting them from your own compost pile, clean the worms by rinsing it at least twice before introducing them to your system or you can purge their system (guts) by putting them in a wetted down cornmeal for 24 hours. Then wash your worms off and introduce them into the system by putting them on top of the grow beds, they will crawl into the media to escape the light. (2)
The best worms for aquaponics are the bright red composting worms that are available online or from your local nursery, not the grey worms in your garden. So keep that in mind, if you want a more balanced and sustainable, maintenance-free system, adding worms to your aquaponics system is a great way of getting rid of the wastes you don’t want in your system. Using vermicompost or vermicompost tea is very beneficial to your fish, plants and helps your system to function more efficiently. Join our Facebook community for more information about aquaponics.