How To Feed and Care for Tilapia in Aquaponics

Tilapia is one of the most cultivated species of fish in the world. Its hardiness, combined with the ease of raising it, has made it the second most raised fish commercially behind the carp. However, there are still quite a few things you should know if you plan to use them in aquaponics.

Here’s how to feed and care for tilapia in Aquaponics:

Choose the correct type of tilapia for you.
Stock/hatch your tilapia the right way.
Use proper feeding practices.
Maintain optimal conditions in the tank.
Set up a filtration system.

As relatively easy as it is to raise tilapia compared to other fish, you must still manage it well if you want to get a functional and efficient system running. So, let’s look into the specifics together and cover every detail so that you can keep your aquaponic tilapia happy, productive, and healthy.

1. Choose the Correct Type of Tilapia for You

There are quite a few tilapia species, and a lot of them are suitable for raising in an aquaponics farm.

Although you can raise most of them perfectly fine in most systems, there’s enough difference between each species that you should know the differences between them before you make a choice.

Choosing the suitable species involves more than just selecting the biggest grower or the hardiest fish. To make the proper choice between the different types of tilapia, it’s best to ask yourself what you can manage efficiently. No matter how big a fish is supposed to get, it won’t get there unless you maintain it properly.

Here are a few criteria to look out for:

Temperature: Choose the temperature that closely matches yours as it’ll save you a lot of headaches in the future. If you live in colder climates, one type of tilapia might serve you far better than another. This condition is the same if you live somewhere warm.
Size: Consider the best size for your system. The first and most prominent of these is your sale price. Bigger fish usually sell for more, so if you’re planning to sell, the size could influence your choice. Also, the bigger the fish, the more feed and waste become involved– which means more cleaning and maintenance.
Taste: Factor in taste if you plan to sell. Tilapia can taste mild or strong depending on your chosen species, so think about the most commonly eaten species when you make your choice.

So, let’s look at some of the best tilapia species for aquaponics and discuss their optimal conditions:

Nile Tilapia (Oreochromis Niloticus)

The Nile tilapia is perhaps one of the longest-enduring tilapia species.

Named for the river that runs through eastern Africa, where they are native, this fish has been reared for thousands of years. Its history in aquaculture spans back to Ancient Egypt.

Typically the Nile tilapia is brown or gray depending on whether it is older or younger. Still, centuries of breeding in agriculture have led to enough hybrids that classifying them based on color can be difficult. It’s far easier to identify the Nile tilapia with its other features.

This fish weighs 1-2 pounds (0.45-0.91 kg) at maturity, although some subspecies can grow up to 11 pounds (4.99 kg). It takes about seven months to get to this point. They thrive in temperatures between 27-30°C (80.6-86°F), a relatively mild temp range.

It’s an omnivorous fish and feeds on a variety of things including, phytoplankton, insects, and plants.

One potential downside about the Nile tilapia is that its meat is mild with not much flavor, so if you plan to sell it for food, you might want to look into one of the other options on the list.

The Nile tilapia is suitable for farmers that don’t want a fish that grows too large and can survive in mild to moderate temperatures. If it’s cold year-round where you live, some species will better suit you, or you might have to pay for extra heating for your tank.

Regardless of its taste, the Nile tilapia is still the most cultured tilapia species globally, as the ease that comes with raising it is nearly unmatched. However, if the taste or size doesn’t fit your requirements, you can still try a couple of other options.

Blue Tilapia (Oreochromis aureus)

The Blue tilapia is so-called for its characteristic blue tinge. Apart from that, it’s similar to the Nile tilapia in many respects, especially visually.

One key area where this species differs from the Nile tilapia is its preferred temperature. As I said, a critical limiting factor of the Nile tilapia is that it’s not a good choice if you live in cold regions. For frosty climes, the Blue tilapia is a much better option.

It thrives in the 12-32°C (53.6-89.6°F) range. It can also tolerate between 8 and 40°C (46.4 and 104°F), although it might not perform as well when you leave it on the fringes of its accepted range.

One other key area where it differs from the Nile tilapia is that it can be reared in saline water even though it’s a freshwater fish. Performance might not be optimal, but it’s something to consider if you plan to go the saltwater route for your aquaponics setup.

Finally, the Blue tilapia weighs almost half the size of the Nile at maturity. On average, it weighs 5-6 pounds (2.27-2.72 kg).

The Blue tilapia is an excellent choice if you live in colder regions and want a hardy fish that requires minimum fuss to raise. It’s also a great choice if you like the Nile tilapia but want a smaller species.

Mozambique Tilapia

The Mozambique tilapia is endemic to southern Africa. Similarly, it’s also like the other tilapia on this list, apart from a few key differences.

One of these differences is in its taste. Unlike the others mentioned, Mozambique tilapia has a strong flavor, and many people choose to cultivate it for this reason.

However, it’s also smaller than the Blue tilapia, growing up to 2.4 pounds (1.09 kg). Temperature-wise it does better than the Nile but worse than the blue. It has its optimal range at 17-35°C (62.6-95°F).

This species of tilapia is also omnivorous, although it’s opportunistic. This tendency means that it’ll generally feed on plant life but feed on animals if it’s easy enough to get. This difference is a crucial point to remember, as larger fish in a system can eat the smaller ones without enough food to go around.

As a result, it’s essential to employ different feeding techniques regardless of the species you plan to raise.

Note: Tilapia are an invasive species. This classification means that when introduced to new habitats where they shouldn’t be, they can cause significant damage up to the extinction of some of the local plant or animal life. Due to this, you should never dump tilapia you don’t need in a local pond or stream regardless of how much more humane an option it might seem than killing it.

2. Stock/Hatch Your Tilapia the Right Way

Once you’ve chosen the proper type of tilapia for you, the next thing to do is to introduce them into the aquaponic system. There are two ways to go about this potentially:

Hatching

Hatching your fish is an admittedly less popular way for new farmers. However, if you have the patience, it can be a great way to breed your tilapia selectively.

Hatching your tilapia means that you grow your own rather than buy new stock. This method is slower, and if you plan to go into aquaponics, it might be a few months before you can reliably produce enough waste to sustain the plants.

However, it’s an excellent way to go if you have existing stock and want to restock after harvest. It eliminates the cost of supplying as you’re repopulating your tank yourself.

Here are the steps to follow if you plan to hatch your own tilapia:

Choose tilapia with favorable characteristics. For reproduction, you’ll need one of each gender. The features to watch out for vary depending on preference, but some good things to watch out for are size, resilience, and response to feeding.
Keep the mating tilapia in a separate tank. You’ll need to reproduce the mating conditions in this tank to stimulate them to mate. For tilapia, this means the tank needs to be kept at a constant temperature of 75-85°F (23.89-29.44°C) with a 12 hour light cycle.
Lay a substrate at the bottom of the tank. Because tilapia fertilize externally, there must be a suitable surface for this. Laying a substrate at the bottom of the tank gives the fish a location to lay and fertilize their eggs.
Separate the fry from the mature fish. Tilapia are opportunistic carnivores, so if you don’t separate the fry from the mature fish, the adults might cannibalize them.
Maintain the fry to adulthood. It’s essential to make sure the fry grows in optimal conditions because the quality of the fish you produce directly impacts the price you can sell them for and the overall health of your aquaponics system.

Note that the best way to run a complete aquaponics system is with mature fish, so you can standardize living conditions and your system size to fit. Because of this, it might be a few months before you can comfortably run an aquaponic system if you choose to hatch your fish yourself.

Stocking

If you don’t have the patience or the need to hatch your fish yourself, your best option will be to stock your tank with fish from a breeder. The significant advantage of using a breeder is the professionalism that comes with it.

Breeders are a lot more adept at breeding specific traits in fish, so if you’re particular about the type of fish you’d like to produce, then a breeder is your best bet.

That said, just because you’re stocking from a breeder doesn’t mean there aren’t still rules to follow. Here are a few things to consider when stocking a tank:

Follow a stocking density of 1-2 fish per gallon (3.79 L) of water. This density provides enough fish that the tank space is efficiently used and ensures that the fish have plenty of room.
Introduce the fish to the new tank gradually. Doing this will allow the fish to acclimatize to their new surroundings.
Quarantine the new stock for 3-4 weeks. If you’re introducing new fish to older stock, quarantine the new ones. If even one of the fish from the new group is diseased, it could cause a problem for the whole population. Because of this, it’s best to quarantine them for observation for a few weeks. Once this time has passed, it should be safe to introduce them to the tank.

3. Use Proper Feeding Practices

Regardless of the species you choose, it’s essential to understand that feeding is likely one of the most critical things to get right to keep your system functioning optimally. Feeding is important enough in any agricultural system, but this is doubly true for aquaponics.

As aquaponics relies a lot on the waste produced from the aquaculture section of your system, it’s critical to feed your fish correctly to ensure that they make the waste in the first place.

The proper feeding practices entail far more than just feeding them enough. Here are some of the things to consider when feeding your tilapia:

Feed Your Tilapia the Right Type of Food

Admittedly, getting the correct type of feed is less critical for tilapia than for other fish species. Tilapia adapt to a wide range of conditions. They have very varied diets, so they’ll be fine as long as you feed them something within their diet.

Pellets are one of the best types of fish food and are welcome by a wide range of fish. If you’re looking for a good, affordable option, then Wardley Fish Food Pellets (available on Amazon.com) are a great choice. They also come in various sizes to account for different stocking sizes.

Incorporate Organic Food

With tilapia, going organic is also an option. There are two ways to go about it:

Supplement the tilapia feed with organic feed.
Make organic feed the primary source of food.

Although the second option is perfectly viable in many other setups, it’s better to go with the first in terms of aquaponics. The main reason for this is that while it might keep the fish alive, it won’t necessarily keep it at the target weight you want.

Because of this, it’s best to supplement rather than depend entirely on organic feed.

Regardless, here are some organic food options for your tilapia:

Duckweed
Moss
Cocoyam Leaves

There are also industrially produced brands that are marketed as organic. This type of feed could be a great option if sourcing things like duckweed proves to be a significant problem.

Feed Tilapia at the Right Time

With feeding, time is almost as important as the quantity and quality of feed you use. Your fish will respond differently to food based on current conditions, stress levels, and various time-related factors.

Generally, you want to feed tilapia three times: morning, afternoon, and evening. You should try to time your feeding to times when your fish are least stressed. For example, if you need to empty the tank, do it before feeding the fish. Changing the water can be a stressor to fish, and many of them vomit digested food when this happens.

To summarize and give you a better idea of what to account for, here are some tips to follow when feeding your tilapia:

Feed them three times daily. Getting the proper amount of food into them is the first way to promote growth and good health. You’ll get the best harvest if you feed them right and maintain optimal conditions.
Feed adult tilapia 1% of their total weight each day. For juvenile fish, feed them 7% of their body weight. Like any other species, younger ones need more food to grow relative to their body mass, and you can level this out as they get older. These percentages are the established guidelines for feeding tilapia, and although you can go above, I’d recommend that you don’t go below.
Don’t overfeed your fish. It might seem like a better option to dump as much food as possible and let them take what they want, but it causes problems like poor water quality and increased stress on your biofilter and grow bed. In extreme cases, it can also cause issues like fin rot.
Schedule change of water in the tank after feeding time. Activities like this can stress the fish, causing them to vomit.
Maintain optimal conditions. If your temperature, pH, oxygen levels, or any other conditions are off, it could significantly contribute to our fish not eating correctly.
Don’t suddenly change the brand/ type of feed. It’s best to test a little at a time first. See how the fish react, and if the reaction is favorable, you can introduce it as an alternative to your previous choice.
Clear out as much uneaten food as possible. If there’s still feed floating at the top of the tank after 5-10 minutes, scoop it out with a net. Leaving uneaten food can cause problems with water quality.
Store your food in safe places. Keep your food in dry rooms to avoid mold and bacterial growth during storage. Also, keep it away from pests and chemicals. Any contamination to your feed will be detrimental to your fish. It could also cause problems with your plants because the water from the tank is recycled.

4. Maintain Optimal Conditions in the Tank

Getting your fish into the tank is only the beginning. Once that’s done, you’ll have to ensure that they grow optimally.

Once you have everything up and running, most of the work you’ll have to do is centered on maintenance. Maintaining optimal conditions in the tank at all times will give you the best possible yield and keep your attached hydroponics garden running smoothly as well.

Here are some of the most critical conditions to monitor:

Temperature: The temperature in a tilapia tank should be optimal depending on the species. You should always try to stay close to the middle of the ideal range. It’s better to do this rather than stay on the fringes since sudden changes in environmental conditions could wreak havoc on your system.
pH: The pH should ideally be around 8. However, because the plants share the same water and usually prefer acidic water to alkaline, you’ll have to use a pH of approximately 6-7.
Water quality: Your water should always be as transparent as possible. Cycle your water regularly and use filters or separators to remove excess solid waste
Food: Feed your fish three times daily. As a guideline, try to account for 1% of total body weight for adults and 7% for juveniles every day.

5. Set Up a Filtration System

Keeping your water clean is beneficial to both your fish and your plants. However, with things like waste, excess feed, and the occasional stray leaf, it can be a little difficult to keep things as clean as you would like.

A filtration system helps with this. If you have a media-filled bed for your plants, then you might not need a dedicated filter. However, pollution could still happen if you overstock your fish and overburden the filtration system. In addition, a reliable filter dramatically improves water quality for most other systems.

There are two types of filters in aquaponics:

Biofilter: This filter ties your aquaponic and hydroponic sections together. It converts the ammonia from the fish tank into usable nitrates for the plants.
Mechanical Filter: The mechanical filter filters out solid waste. This removal protects the biofilter and prevents potential clogging.

Both types of filters are essential if you want to keep your tank as clean as possible for your fish. Tilapia are hardy and are more tolerant of dirty water than other fish. However, keeping the tank clean is still critical.

Should You Raise Tilapia in Aquaponics?

With everything that goes into raising tilapia, you might start to wonder if it’s worth it. There are many types of fish to choose from for an aquaponic system, but most of them are significantly more challenging to raise than tilapia.

You should raise tilapia because they’re a relatively easy, resilient choice. Tilapia are particularly easy to cultivate, and for an aquaponic system where you have to monitor so much more than just the fish tank, they’re a great option.

For newcomers to aquaponics, tilapia is a great choice. Easy-to-manage fish are one of the best choices you can make for an aquaponic system to thrive. The less time you spend on your fish tank, the more time you have for the rest.

That said, if tilapia still don’t appeal to you, here are some alternative fish you can use in aquaponics:

Carp
Catfish
Trout
Koi

Final Thoughts

Tilapia is a great, resilient choice for beginner and veteran aquaponic farmers alike. Most of the heavy work involved is at the start, and once you get a stable system running, maintenance is usually low and manageable.