How to Use Aquaponics to Grow Fish

Are you looking for a method to use aquaponics to grow fish? Irrespective of whether you want to grow ornamental or edible fish, raising them alongside plants is easy and quick. The water system uses the natural process of converting the ammonia from fish waste into nitrates and nitrites, which can then be added as fertilizer for plants. It’s an eco-friendly system that can benefit both the environment and your bank account.

Aquaponics is not just about raising fish; it’s also about gardening with minimal effort. With this type of system, you’ll find yourself spending more time enjoying fresh produce than sitting in front of a computer screen. It may be too good to be accurate, but if you want to learn how to employ aquaponics to grow fish, check out our blog post.

What Should You Know Before Using Aquaponics To Grow Fish?

Starting aquaponics to grow fish? Here are a few things that you must remember.

Fish Edibility

Fish edibility will play a significant consideration in your fish species selection. If you’re planning to eat the food, build an ecosystem around edible fish such as tilapia and catfish. But these can be more challenging than other options with specific conditions that need attention from their owners. For example, carp need high protein foods such as soybeans or lentils, while largemouth bass prefers softer waters.

Goldfish are great for anyone who wants an easy-to-maintain, disease-resistant fish that can be used in a smaller or indoor aquaponics system. However, Goldfish are not edible fish.

Tilapia Aquaponics Fish


If you want a fish that can survive in your area’s climate, it will have to thrive too. Some live well at cool temperatures, while others prefer warmer waters with less fluctuation from season to season or day to a year. But they all must fit into some range within which they’re comfortable when using aquaponics to grow fish. 

Fish can thrive in an aquaponics system as long as they are kept within their desired temperature range. A steady, stable environment with changes that keep the fish healthy and growing faster will help you select a good variety for your garden.


When hand-picking the best fish for your aquaponics to grow fish, consider their availability and ease of acquisition. Some are only available in some areas while others can be found all around the world. The most common type used for this purpose would be Tilapia due to its hardiness and wide distribution across many regions.


You may think that you’re safe to buy fish from the store, but it’s essential to ensure what kind of water they were raised in. Some locations have strict laws on which types of aquatic life can be sold or owned, so ask your local authorities about this firsthand before purchase.

Size and Space

To keep the right kind and amount of fish, you need an aquaponics fish tank that’s big enough. Adult sizes are essential so make sure they’re known before adding any new crew members. For instance, The channel catfish is a fish that can grow up to 50 lbs. This means they need at least 250 gallons of water, so you’ll want plenty available for it in your tank.


The capacity of your aquaponics to grow fish is determined by the filtration ability. You should balance the fish needs and plant requirements in a way that doesn’t overpopulate or under-populate either one too much. Or it can disrupt water oxygen levels for both plants and animals alike. Your general rule would be about 1 inch per gallon (or more) when keeping them together, but if you think you’re running low on space, just go ahead and add some more.

Breeding Habits

If you want to have high-quality fish, the breeding habits of each type must be carefully chosen. Some species don’t reproduce in captivity and may cause problems for your aquaponics system if they’re raised too densely. Other types like Tilapia can do well even when being bred quickly because this doesn’t stress them out so much, making more space less necessary.

Water Quality

The quality of the water is too important when considering aquaponics to grow fish:

  • Ammonia. Ammonia is harmful to the fish when its levels surpass 1 mg/litre. Biofilters and beneficial bacteria are used for converting ammonia and nitrates, and nitrites.
  • pH: Although fish can withstand a wide range of pH, the best pH level for all types of fish is 6.5 – 8.5. pH stability is also crucial. Some use buffering with carbonate for stability. 
  • Dissolved oxygen: A DO of 5ppm, or higher is necessary for the healthy upbringing of fish. In case it is low, you can increase it using a larger pump or air stones. Avoid overstocking. 
  • Light and darkness: Light is an essential element. A too dark tank can make fish species feel stressed and fearful when exposed to light suddenly.

Fish Type

It’s important to understand the difference between a sensitive fish and a hardy one if you want your aquaponics system up and running in no time. For example, Tilapia are hardy but not so much as they’re delicate towards diseases or parasites, making them pricey maintenance-wise, while Koi has both great qualities. It is robust with immunity against such ailments making it perfect for beginners to invest their energy into something worthwhile rather than constantly worrying about what might go wrong next.

Now that you are familiar with the things you must know, it is time to learn about the various types you can use aquaponics to grow fish for.

Best Fish for Aquaponics

To receive the most out of your aquaponics system, grow only the best fish for aquaponics. Some of them are listed below. 


Tilapia is an excellent choice for aquaponics because of their hardiness and ability to grow in less than ideal water conditions. Tilapia is resistant to many pathogens, parasites, handling stress that other fish might experience when grown indoors (and can even tolerate low levels of ammonia). Since this omnivore eats both plant-based feeds as well animal-based ingredients, it truly makes them a versatile species.

The Tilapia harvest time varies depending on the water temperature, food given, and size of your desired catch. It’s easy to breed these in an aquaponic system when they prefer a pH level between 6.5-9, with 82°F – 86 degrees Fahrenheit being optimum conditions for breeding them.

Tilapia Aquaponics


Trout is a perfect fish for indoor and outdoor systems. They have an excellent temperature range, prefer colder water (56-68°F). While slower growing than many types, trouts can grow up to about 1 pound per 4 years.

Trout are freshwater fish that can survive in both brackish and saltwater environments. They thrive best with higher protein diets, but the most important characteristic is their tolerance for salinity levels which make them perfect additions to an aquaponic system no matter where you live.

Trout Aquaponics


For those who want to use aquaponics to grow fish, catfish are one of the most favoured. They can withstand wide swings on DO levels and pH and high temperatures without suffering adverse effects like other types. They might do so when they’re overexposed, but don’t get this type wet.

Catfishes have resistance against many diseases due to their hardiness; however, new pathogens may still affect them. They’re bottom feeders that scavenge for food on the ocean floor or among other fish. Catfishes can be difficult to breed because they don’t have a lot of territorial behaviour but make sure your tank has more horizontal space than vertical since these guys like living out at sea level.

Catfish Aquaponics

Largemouth Bass

The largemouth bass is a tricky fish to keep. They can tolerate wide ranges in temperature, low DO levels, and even extreme pH conditions that kill other types of freshwater organisms. But these creatures prefer clean water, so you’ll need an aquarium with at least one constant flow through it, or else they won’t thrive. These carnivorous inhabitants also require high-quality foods. The growth rates depend mainly on how warm it is (or isn’t!) within their enclosure. Make sure your home’s heating system has plenty of fuel before housing them.

The largemouth bass is a hardy fish that can thrive in temperate climates. It thrives when the water temperature reaches 65 – 80 °F (18-27°C) with pH 6 – 8, and may be harvested within one year from fingerlings if appropriately raised.

Largemouth Bass Aquaponics


The most popular freshwater fish type for aquaponics is koi. These hardy creatures have a long life span and can easily reproduce within your system, which means that you won’t need as much room to house this variety. Plus they’re resistant to many types of diseases or parasites common in other tanks, implying less work on maintaining good hygiene practices when it comes down to them living with others at close quarters.

The advantage of carp/goldfish is their adaptability. The variety in the diet of koi fish is an essential factor when considering their care. They can feed on algae, plant matter, and fallen debris, which gives them the natural independence that many other breeds do not have.

Koi Aquaponics

Challenges Associated With Using Aquaponics To Grow Fish

Aquaponics has many benefits over traditional methods, such as being more sustainable due to its reliance on recycled sources; however, it has downsides.

  • The nitrates in the water can be harmful to the fish. Higher dissolution can cause overstimulation or mutation, which is never good for an aquatic organism. You should make sure that level stays below 25ppm at all times. So, no more than 50 if you want anything else besides algae making up most of what’s there already (and 10% max).
  • Contamination in an aquaponic system is a very big threat because the same water recirculates to fish tanks and beds. Contaminants can quickly spread throughout this delicate ecosystem with disastrous effects for plants/fish living there.
  • Conventional pesticides in aquaponics systems are a complete no-no. These may cause toxicity for fish and other desired biofilm production due to their toxic nature when applied throug

Summing up

Aquaponics is a promising system for the future. It has been used to grow fish in commercial settings, but it can also be efficient for individuals looking to produce their own food without chemicals or pesticides. Those interested in learning more about aquaponics fish and how this sustainable food production method could assist you to have your own produce, this article on “how to use aquaponics to grow fish” should help you.

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Welcome to The Aquaponics Guide

Hello! We are the Johnsons and the faces of The Aquaponics Guide. We have been avid gardeners for many years and growing our own food is one of our key priorities. We have found sustainable Aquaponics farming to be a life changer, which is the reason we have created The Aquaponics Guide. 

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