When you think of growing food at home, you will likely imagine a large garden filled with crops and trees. But in recent years, people have invented new, more efficient, and less space-consuming methods to grow food in the convenience of your home. Enter hydroponics and aquaponics.
Hydroponics and aquaponics are great alternatives for safe food growing even when you don’t have a parcel of land. These methods completely cut out the need for soil, which also eliminates a lot of soil-related issues!
Although hydroponics and aquaponics use the same principle, there are a few key differences in how their system works. It can be confusing to start, and it’s hard to pinpoint which method suits you best. In the article below, you’ll learn all about the most significant difference between these water-based systems.
Table of Contents
What is Hydroponics?
“Hydroponics” came from the Latin word “working water.” It is a soilless system that explores nutrient-rich water to grow crops instead of a growing medium and organic matter.
Contrary to traditional growing practices, hydroponics make the use of soil nearly redundant and make nutrients available directly through water.
Pros and Cons of Growing in Hydroponics
Pros
Hydroponics can work vertically, yielding significantly more crops per square foot than regular farmlands, which can save room on arable land. This also makes it possible for home-growers to grow many fresh veggies and fruit in their small space or garden!
In hydroponics, the plants are also less prone to diseases and weed competition, as these issues typically occur in soil. Using herbicides and chemicals to treat diseases is less needed, leading to sustainable and healthy produce.
Another great added benefit of hydroponics is that it saves water! The water in hydroponic systems is constantly re-used and optimized rather than drained off and discarded, as in traditional gardening.
Cons
The only disadvantage is that the crops you can grow are limited since certain root veggies, like potatoes, need soil to thrive.
Hydroponics may also be more expensive than regular gardening, not only to set up, but the constant need for electricity in the form of a grow light and pumps makes it quite a pricy situation.
Different Types of Hydroponic Systems
1. Wick System
The wick system uses a soft fabric (or nylon in some cases) to bring the nutrient solution to the roots of the plants.
The advantage is that it introduces the solution to the plants slower than submerging the roots, which reduces the risk of burning the roots and offers a constant, solid supply of nutrients.
2. Deep Water Culture System (DWC)
As its name implies, deep water culture completely submerges the roots into a nutrient-rich solution. Typically, the plant will ‘float’ or hang above the water while the roots freely grow into the nutrient-rich water.
Since the roots will grow in water constantly, this system requires an air pump to introduce oxygen to the plant’s roots.
3. The Kratky Method
This is a modification of the Deep Water Culture System, and it’s incredibly popular due to its low maintenance care. The Kratky Method is a form of passive hydroponics, meaning you can simply set and forget this system.
This method uses a net pot inside of a pot with a water reservoir. As the plant grows, it uses the nutrient solution, creating an air gap between the plant and the water level.
This allows the plant to transpire and creates airflow. When the plant has used up the nutrient solution, it is ready for harvest.
4. Nutrient Film Technique System
The Nutrient Film Technique System or NFT System has the same components as the Deep Water Culture, but in NFT, the roots sit in a constantly circulating stream of water. The nutrient solution constantly moves, thus introducing new oxygen to the roots.
5. Ebb and Flow/ Flood and Drain Systems
The Ebb and Flow System is like the NFT System, except the nutrient solution is not constantly moving.
The NFT System uses a continuous stream of water for the plants while Ebb and Flow floods the plant roots for a certain time and then drains for oxygen uptake.
A timer is attached to a submersible water pump to schedule the water flow to the flood tray.
6. Drip System
For this method, plants must live on an inert medium like peat moss or coco coir. The plants are continuously fed a high-nutrient solution through trickles or small droplets.
The goal is to ensure the system conserves as much water as possible! The water that drips from the bottom of the planters will be reused.
7. Aeroponics System
In this type of hydroponics system, the roots receive moisture and nutrients through mist rather than a complete body of water. It uses less water compared to other hydroponics systems!
The plants grow in a small growing small, either in a vertical or horizontal space. The root system can grow freely in the air as they are constantly misted with nutrient-rich mist.
What is Aquaponics?
Aquaponics combines aquaculture (fish farms) and hydroponics for sustainable food production, using the added benefits of fish to grow plants in a symbiotic relationship between plants and fish. The fish’s solid waste feeds the plants, and the plants clean and filter the water for the fish!
Pros and Cons of Growing in Aquaponic Systems
Pros
Aquaponics share many benefits as the previously mentioned hydroponics. It uses less space, reduces the risk of pests and diseases, thus high yields, and saves water.
Unlike hydroponics, aquaponics does not need additional fertilizing, as the plants can grow from the aquatic solution from fish waste alone. This will save money as you do not need to buy chemical fertilizers.
Aquaponics also produces two food groups: vegetables and protein (aquatic animals, or fish) in one go with nearly zero waste, as everything is constantly being reused, so it is a very sustainable and low-waste method for growing food!
Aquaponics may have a lower risk of developing root rot than hydroponics. Root rot is rare in aquaponics setups, but it is a common issue that hydroponic growers must face.
Cons
However, this also makes it less customizable to tailor specific plant’s needs, and it can be hard to properly regulate the pH and nutrient level in the plant’s water.
Additionally, you’ll need to closely monitor the water temperature and electrical conductivity (EC) to keep it at the right range for your specific fish.
However, the biggest downside of aquaponic gardening is that it takes a lot of knowledge, is quite expensive, and has especially high startup costs. If you harvest your fish, you’ll need to replace them.
The necessity of a fish tank also makes it less suitable for home-growers unless you already have a fish pond. Aquaponic methods are commonly used for commercial scale growing.
Different Types of Aquaponic Systems
1. Media Bed
The Media Bed is the simplest aquaponics set-up. The plants are held up by growth medium like pebbles and gravel. This grow bed offers the plants’ roots support.
The nutrient-rich water from the fish tank is brought to the plant through a pump, draining back to the fish. In this method, the plant roots are suspended with air gaps and can access water and nutrients.
2. Deep Water Culture (DWC)
The Deep Water Culture, or DWC, is the same as the media bed system except that the roots are continuously submerged underwater.
The DWC uses a separate filter tank to clean water before pumping it up the plants. It is more efficient than the media bed setup, so commercial growers usually use it.
3. Nutrient Film Technique
The NFT Aquaponics feeds the plants through a constant flow of thin films of nutrient-rich fish water like in NFT Hydroponics. The key difference is the source of plant food.
In NFT hydroponics, a liquid nutrient solution is used, but in NFT Aquaponics, the plants depend on the fish for nutrients.
Hydroponics vs Aquaponics: Key Similarities
You may have noticed that hydro- and aquaponics have a couple of similarities. Below, we will take a closer look at overlapping factors in these two growing methods.
Both Are Soilless Systems
The idea of these technologies is to grow food even without using soil. They have many advantages when compared to traditional methods.
These alternative farming techniques require less space, save water, reduce waste, and lower the risk of weeds, pests, and diseases.
Each Provides Higher Yields than Growing in Soil
Plants don’t spend energy looking for water and nutrients in hydroponics and aquaponics technology.
Instead, they are directly fed through nutrient-rich solutions, which you can easily adjust depending on the plants’ needs at any time!
As a result, the growing of plants takes less time and is more efficient than traditional agriculture.
Can Fit in Small Spaces
Hydroponic and Aquaponic systems can function vertically, making growing many plants without using much space possible.
This also greatly increases the yield per square meter, as you can grow up to ten times as many plants without using more horizontal space.
Both Allow for Harvesting Year-round
Since these methods are made to function indoors, without seasonal influences, you can grow food throughout the year, even during winter. No more waiting for summer to enjoy fresh food and veggies or fruits!
Hydroponics vs Aquaponics: Key Differences
Despite many similarities, hydroponics and aquaponics are very different systems with their own needs and requirements. Below are the most significant differences between these two methods.
Cost and Basic Knowledge
Since aquaponics require an extra but vital component (the fish), it can be much more difficult to set up, and the growing of fish is an added cost that you must consider. You’ll need to create ideal environmental conditions for both plants and fish.
Air pumps, an air stone, and biofilters are necessary to keep the fish healthy, making aquaponics much more complicated, pricy, and less suitable for small-scale farms and home-growers.
Source of Nutrients
Where hydroponics relies on chemical nutrients, aquaponics uses organic nutrients in the form of fish waste. Although raising fish is a much more organic and sustainable method to fertilize plants, it can be tricky to properly regulate the pH and nutrient levels in your water solution.
Certain types of crops may also be unsuitable as fish emulsion alone might not produce enough nutrients for these plants. However, aquaponic growing systems might be the best way to grow food if you prefer to grow simple, non-fussy plants and want to be as sustainable as you can.
Extraneous Growing Media
Another main difference is that a hydroponic system can function without any substrate or growing media, while aquaponics requires the plants’ roots to grow in a soil-like medium.
This is because for the fish waste to be effective, there need to be beneficial bacteria present to convert fish ammonia to available nutrients. These bacteria live in soil and cannot survive in water alone!
Water Chemistry
The bulk of the hydroponic solution is water, where plants get its hydrogen and diluted oxygen. The rest are macronutrients nitrogen (N), phosphorus (P), potassium (K), and other elements such as calcium and magnesium, which all come in different ratios from manufacturers.
Ammonia is the immediate by-product of fish from degrading protein. Although this helps plants obtain their essential nutrients, high ammonia levels are toxic to the fish in large concentrations in the tank. Therefore, constant monitoring may be necessary, especially in commercial production.
pH Levels
The hydroponic setup only considers the optimum pH range of 5.5-6.0, where most hydroponic crops grow. On the other hand, aquaponics must simultaneously consider both optimum pH levels for the plants and fishes. It can be hard to achieve this balance so this system may need much monitoring.
Oxygen Levels
The plants in the hydroponics system must have at least 5 mg/L of dissolved oxygen to survive. In a study on lettuce, 20-30 mg/L of dissolved oxygen improves their yield under low temperatures.
In aquaponics, 5-8 mg/L of dissolved oxygen is needed for beneficial microbes and bacteria to maintain nitrification (transferring fish ammonia to available nitrogen for the plants).
Most fish species require at least 5 mg/L of dissolved oxygen, but cold-water fish may require at least 6.5 mg/L, so an air pump is necessary to provide extra oxygen. The level of oxygen in the tank affects the productivity of the fish.
In short, maintaining the right oxygen levels in aquaponic setups is tricky and will take a little more effort to maintain and balance.
Plant Growth
Plant growth in hydroponic farms is faster than in aquaponics because the nutrient solution is optimized for the crop needs. Premix solutions can be bought for specific crop needs.
Sadly, plant growth can be slow in aquaponics, especially at the beginning of the establishment. The plants’ nutrients depend on the size, volume, and species of the fish you wish to culture.
Pest Control
Although both systems have a significantly lower risk of pest infestations than soil-growing, the plants are not automatically immune to thrips, spider mites, or aphid outbreaks.
Pests are easier to treat in hydroponics because, for aquaponics, you need to consider the fish’s health when purchasing and applying pesticide products. Natural remedies for pests (beneficial insects) are a pretty easy fix to this problem.
The 5 Best Plants to Grow in Soilless Agriculture
Herbs
Leafy herbs like mint, basil, thyme, and cilantro are incredibly easy to grow in hydro- or aquaponics. They require little space, so they’re great for beginners and urban areas.
These plants will grow incredibly fast in a soilless medium, so you’ll never be without fresh herbs to add to your favorite dishes!
Due to this fast growth rate, herbs are recommended for an aquaponics system because the nutrient available in the water is limited to the fish manure.
Lettuce
If you’re an experienced gardener, you may know how easy lettuce (and other leafy greens) are to grow, just like the flowering houseplants, in the soil too!
What if I told you they’ll be even easier if you grow them in hydroponic growing methods? Due to their shallow roots, they are very suitable for systems like the NFT method.
Strawberries
Strawberries work well in hydroponic systems since their nutrient requirements are low and easy to maintain.
These summer berries will grow well in almost every system design, but a DWC or Ebb and Flow method would work optimally to keep these plants lush.
Tomatoes
You can enjoy homegrown tomatoes year-round by using hydroponic or aquaponic systems.
Tomato plants will grow much faster in a hydroponic system than in soil, so they are a great option for impatient gardeners like myself. Tomatoes can grow in all different systems.
Cucumbers
Although cucumbers are a summer crop, you can grow them in your hydroponic growing system whenever possible.
They grow fast and are less vulnerable to soil-borne diseases as they grow in water. Other squashes like Zucchini can also do well in hydroponics!
Plants That Won’t Do Well In Soilless Systems
Root Vegetables
Root veggies like potatoes and onions might not perform well in hydroponics, as they have high nutrient needs that are hard to meet in soilless systems.
Additionally, they require a lot of room to vine and grow. Although it can be done, traditional soil gardening might be a better growing method for these specific plants.
Large Fruit Trees
Lemon trees, apple trees, and orange trees. These beautiful trees will grow some of the most delicious and nutritious fruits available, but sadly, they’re not great in hydroponics.
They are simply too large and demanding for hydroponics. They grow slowly and are not suitable for indoor growing.
Conclusion
So, what’s the best soilless way to grow plants? Well, it depends on how invested you want to be. If you’re a beginner who wants to try soilless growing at home but doesn’t want to spend too much, try the wick system or the Kratky Method. You can find hydroponic kits online to get started!
If you’re determined to venture into technology, try the deep water culture system, NFT System, Ebb and flow system, aeroponics, or drip system.
If you’re in for an extra challenging project, we suggest investing in an aquaponics set-up. Whichever method you pick, we are sure that growing your own food will be a rewarding experience for you.
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