When considering the use of fish emulsion in hydroponics, it is advisable based on its nutrient composition. This liquid fertilizer, known for its thickness and weight, is recognized for supplying hydroponic plants with proteins, amino acids, and oils. Nevertheless, it is important to take into account the drawbacks, such as its unpleasant odor.
Before we delve into a comprehensive discussion, it is important to familiarize ourselves with the concept of fish emulsion.
A fish emulsion is a fertilizer that can be created using any combination of a fish’s internal parts, external organs, or even the entire fish.
Fish emulsion, a widely known fertilizer made from processed fish, is familiar to most gardeners. Those who have fish, whether in an indoor aquarium or an outdoor pond, may question the benefits of feeding their plants with fish waste. The practice of using fish waste as a fertilizer has been in existence for a significant period and is a key advantage of aquaponics. However, how exactly does fish waste contribute to the growth of plants?
How Does Fish Waste Help Plants Grow?
Using fish waste for plant growth has several benefits. Fish waste refers to the fecal matter of fish and, similar to manure, it contains abundant biological activity and a balanced combination of essential plant nutrients and micronutrients. Therefore, when plants are fed with fish waste, they receive the nutrients they require as well as an abundance of beneficial biological life in the soil. Additionally, using fish waste as a fertilizer is a quick and efficient method as it is in liquid form, allowing for faster nutrient absorption compared to solid fertilizers.
Is Fish Poop Good For Plants?
It is logical that fish waste is beneficial for plants, as fish emulsion made from plant waste is a widely favored organic fertilizer. When fish waste is utilized for plant growth, it supplies not only naturally derived NPK nutrients but also micronutrients.
Some commercial brands of fish fertilizer have been found to have chlorine bleach in them, which is not suitable for a garden. However, if you have a pond or aquarium and feed your plants with fish waste from it, it is the best option, as long as you don’t use herbicides on the lawn around the pond.
Why Is This Important?
One of the main reasons plants die, especially in hydroponic systems, is due to a lack of nitrogen. Nitrogen is essential for leafy hydroponic plants like lettuce, kale, bok choy, and spinach as it plays a crucial role in promoting leaf growth, color, and development.
There is a reason why fish emulsion is the best choice for leafy vegetables and herbs.
5 Pros of Using Fish Emulsion in Hydroponics
Fish emulsion is highly beneficial in hydroponic systems due to its organic nature, mildness, nutrient content, effect on beneficial microorganisms and growth hormones, as well as waste reduction.
- Organic
Because fish emulsion utilizes environmental wastes from fish, it presents a superior alternative to synthetic fertilizers. As a result, hydroponic farms that use fish emulsion have the opportunity to seek organic certification and designate their produce as organic.
If you are considering organic hydroponic gardening, fish emulsion is a suitable choice. Additionally, some organic farmers opt to incorporate seaweed extract with it.
- Mild Fertilizer
Because fish emulsion has a mild concentration and a low nutrient ratio, it is considered suitable for beginners. This is because many hydroponic nutrients still necessitate computation or conversion, which can potentially discourage gardeners from utilizing them.
The nutrient analysis of fish emulsion showed that it has a ratio of 2:4:1 for nitrogen (N), phosphorus (P), and potassium (K). This indicates that the fish emulsion fertilizer is gentle and poses a minimal risk of leaf damage or burning in hydroponic plants.
Therefore, if you are unsure or lack experience with synthetic or hydroponic fertilizer, a straightforward option to feed your hydroponic plants frequently would be to use fish emulsion fertilizer.
- High Nutrient Content
It has been found through analysis that a standard fish emulsion may consist of a ratio of nitrogen (N), phosphorus (P), and potassium (K) of 2:4:1. Additionally, micronutrients including magnesium, chlorine, sulfur, calcium, and sodium have been identified.
Using fish emulsion in a hydroponic system aids in nourishing the nutrient water. If you are growing multiple plants, it can be included along with other hydroponic nutrients. This method is particularly suited for commercial gardening in nutrient film technique (NFT) hydroponics.
In smaller systems like deep water culture (DWC), the nutrient water can solely consist of a diluted fish emulsion solution.
- Precursor for Plant Growth Hormones
By activating the production of plant growth regulators like auxins, cytokinins, and gibberellins, fish emulsion promotes the control of leaf, flower, and fruit development in hydroponic plants.
Plant growth hormones might not be a familiar concept to you at the moment, but think of them as being akin to the four fundamental elements: water, fire, earth, and air.
Is it accurate to say that these elements have separate roles in our world? Nonetheless, when they are combined, they contribute to human progress.
Now, let’s delve deeper into the mentioned examples of plant growth hormones.
- Auxins. They primarily regulate growth by increasing cell size. They can act as both growth stimulators and growth inhibitors for roots, stems, and buds.
- Cytokinins. They play a role in plant cell division, cell enlargement, senescence (plant aging), and growth.
- Gibberellins. They control cell length and division in plant stems. They also stimulate the making of ribonucleic acid (an important chemical for plant genetics) and protein (a macromolecule responsible for growth) in plant cells.
- Reduces Wastes
By utilizing fish emulsion, the waste generated from fish scraps can be transformed into fertilizer, minimizing wastage. This becomes advantageous for hydroponic gardens established at home, as it allows for the utilization of kitchen waste.
In most instances, fish wastes are typically thrown away. Consequently, converting them into fish emulsions serves as an effective approach to achieve harmonious resource management.
To put it simply, our process involves cultivating fish, consuming them, converting their body parts into fish emulsions, and using the resulting nutrients to feed our hydroponic plants.
4 Cons of Using Fish Emulsion in Hydroponics
Drawbacks of utilizing fish emulsion in hydroponics include its elevated price in comparison to other hydroponic nutrients, its unpleasant odor, the necessity for reapplication, and its contradiction with vegan principles.
- More Expensive Than Other Fertilizers
The market prices for fish emulsion are relatively higher, amounting to 35 USD. In particular, it is pricier in comparison to liquid hydroponic solutions, which are priced at 30 USD and below.
- Has Unpleasant Odor
Because fish emulsion is derived from fish components, the presence of an unpleasant smell could greatly distress hydroponic gardeners, particularly those who have established their hydroponic setups indoors, where the lack of proper ventilation limits airflow.
The presence of this factor can be anticipated as the fish emulsion ingredients inherently possess a fishy smell. Due to being derived from fermented fish, it emits a noticeably strong putrid odor.
If you use fish emulsion in large amounts or without dilution, it is likely to cause irritation to those around you, whether it be your family or a neighbor. Therefore, it is advisable to apply fish emulsion when there are no other individuals present.
Additionally, your hydroponic garden can be enticing to flies and cats.
- Needs Frequent Reapplication
Compared to other hydroponic solutions on the market, fish emulsion has a low nutrient ratio, making it a relatively weak solution. As a result, gardeners need to reapply it twice a week, which adds extra work.
Some individuals might inquire, “Is it possible to simply increase the amount of fish emulsion and use it once every week?” or “Can I decrease the concentration instead of needing to reapply it?”
The main issue we are currently dealing with is the strong odor of fish emulsion. When you decrease the dilution, the unpleasant smell becomes even more noticeable. Therefore, it is not recommended to decrease dilution or increase the amount of fish emulsion.
- Against Vegetarian/Vegan Principles
The use of fish emulsion in hydroponics could be seen as contradictory to the principles of individuals who follow a vegetarian or vegan lifestyle, as it involves harm to animals during the food production process.
If you are a vegetarian or vegan hydroponic grower, you have the option to use dry or liquid hydroponic nutrients that can be found in the market. However, if you prefer to maintain an organic approach, utilizing liquid seaweed extract is also a fantastic alternative.
3 Questions to Ask Before Using Fish Emulsion
Before deciding to purchase fish emulsion, it is imperative to inquire about the garden scale, economic value, and odor.
Now, let’s determine whether using fish emulsion would be a suitable option for your particular hydroponic setup.
- Is it more practical to use fish emulsion than natural hydroponic nutrients?
If you are cultivating leafy vegetables on a small scale, then opting for fish emulsion would be a suitable decision.
When considering the options, it is important to assess if there are other alternatives that are less expensive and more effective, such as liquid hydroponic solutions or dry nutrients. These alternatives generally have higher concentrations and nutrient ratios.
- Can my family and neighbors handle the bad odor?
Furthermore, seeking input from your family and neighbors is necessary when making this decision since applying fish emulsion in your garden may generate unpleasant smells that could potentially upset those nearby.
- Am I growing small-scale or large-scale?
When growing in a small-scale garden, fish emulsion is used as the only component, while in large-scale gardens like commercial lettuce farms, it is only used as an addition.
In order to determine how much you will need, it is important to ask this question. This will enable you to assess whether you require a small amount or a few extra gallons of fish emulsion.
How to Use Fish Emulsion in Hydroponics
The key to using fish emulsion in hydroponics, regardless of the application type utilized by a gardener, lies in the process of dilution.
Using fish emulsion as a foliar spray.
- Dilute 1 tablespoon of fish emulsion for every gallon of water.
- Place the solution into a spray bottle.
- Spray it on your plants twice a week.
Fish emulsion is most effective as a foliar spray for leafy vegetables like lettuce, spinach, bok choy, and kale due to the leaves’ ability to absorb the nutrients present in the fish emulsion.
There are two methods in which fish emulsion can be used as a water additive in hydroponics.
- For large-scale gardening:
- Dilute 1 tablespoon of fish emulsion in a gallon of water.
- From the diluted solution, get a teaspoon and mix it with your hydroponic solution.
- For small-scale gardening:
- Measure 1 teaspoon of fish emulsion.
- Mix this amount to every gallon of water your reservoir has. For example, 4 teaspoons for a 4-gallon hydroponic reservoir.
Summary of Fish Emulsion in Hydroponics
Fish emulsion is highly beneficial in hydroponics due to its organic, mild, and nutrient-rich composition, which not only promotes plant growth but also reduces waste.
Using fish emulsion in hydroponics also comes with disadvantages including its expensive cost, unpleasant scent, requirement for frequent application, and goes against vegetarian/vegan beliefs.
Before purchasing fish emulsion, take into account the scale of production, economic worth, and smell. To utilize it, mix 1 tablespoon of fish emulsion with 1 gallon of water. You can apply this on the leaves, as an ingredient in hydroponic water for extensive gardens, or as the only element in a hydroponic solution for smaller gardens.
