Photo-bioreactors for tilapia in Brazil, a reality

Why did you decide to go into the tilapia business? Sergio Zimmermann- In 2003, the shrimp market prices were falling.   I convinced Ari that tilapia would be a safer and cheaper alternative. In 2004, there were two major outbreaks of White Spot Syndrome and Taura Syndrome in the area of Laguna. It was a great tragedy for shrimp farmers because they lost all their production, twice.

How did the market receive this new product?

SZ- People in the south of Brazil didn’t consume tilapia. The company had to develop the market. We created a promotional campaign, giving away the product for free at the supermarkets; this campaign was so successful that eventually we had no more product, so we needed investment in order to grow. Currently, the company and the brand Fish-Sul are incredibly valuable, but it took almost 7 years to get to this point.

Do you have competition?

AP- Yes, there is competition, but not locally, everything comes from Sao Paulo. There are also restrictions that prevent tilapia from being imported from countries like China. 

How is the tilapia market in Brazil?

 SZ- The Brazilian market is not like the mexican market. In Mexico it’s easy to sell small tilapia, of about 250 g, for consumption by class C population. In Brazil, people hardly consume whole tilapia; the vast majority of production is for fillets.

AP- Tilapia fillet in Brazil sells for about 18 reales (USD $11) per kg. It takes 4 months to reach 300 g, and we have three annual harvests. Selling only fillet has its advantages, because it’s a stable market, but it also requires large investments in infrastructure for processing plants; we currently don’t have a plant of our own, because our production didn’t justify the costs of such infrastructure.

SZ- Fillets also have many disadvantages, as a big part of the fish is wasted if people don’t know to process it well; there is also a lack of control in quality, and it increases the costs of production. The one that earns real money is the retailer; they can make a profit of up to 60%.

Alternatives for tilapia marketing

What are the alternatives for the marketing of tilapia in Brazil?

AP- Tilapia for sushi and sashimi is a very important production, as there is a great demand for white fish. There is short supply, as fish such as sole fish and other species are very expensive.

For this market, we need a 1 kg fish. As the customer will sell it already prepared, for a similar price to those of salmon or tuna, they will get a good profit, so we want to sell them the whole fish and the customer will absorb the waste.

Can tilapia fillets compete in this market?

SZ- Yes. For example, you can start freezing the fish; by not freezing it completely, the meat will be a little firmer and you can obtain a very thin, white, mild flavored fillet.

AP- The advantage of tilapia over more expensive fish as sole is that sole is sold in large pieces, and if not used, the unused portion is wasted. Instead, a restaurant can buy a small tilapia daily, and it will be always fresh.

SZ- This market is pretty new. It has not arrived to cities such as Sao Paulo, where there can be a great demand. However, given the population of Asian descent in the country, especially in the state of Paraná, tilapia is already much consumed, and it has been adapted to local recipes. By instance, there is a common dish with tilapia and cabbage. 

Biofloc farmsHow many companies in Brazil use Biofloc?

AP- In southern Brazil there is one or two companies that use this technology, but they are very small. In Sao Paulo there are a few too. This is due to a lack of infrastructure. 

Tell us about your production.

AP- We produce 6 to 8 t of fish per month. We also sell larvae and juveniles, which allows a faster return of investments but also takes spaces that could have been used for growing adults. We finally decided to grow the business and we will buy our own processing plant. 

The fish is harvested at about 600 g, which produces a 100 g fillet. If we harvested at 1 kg, we would get bigger fillets, but the production costs would be higher too.

Do you receive governmental support?

AP- It is primarily financing, not for capital grant. In Brazil, non-refundable loans are only for products related to aquaculture, such as aerators, but not for plant development. The government manages long term grants, but eventually we have to pay every cent.

Have you faced any problems while trying to expand your company?

AP- Our major problem is the lack of a processing plant where we could fillet our own product.   If we had our own plant, we would demand more raw materials and boost the growth of the industry.

Features of Biofloc aquacultureWhat are the advantages of production with Biofloc?

AP- The main advantage is the good feed conversion ratio (FCR). The ideal level is reached at 600-700 g; when working with Biofloc, we can achieve a 1:1 FCR. If we didn’t use this system, we would get a 1:1.4 FCR.

SZ-Biofloc is much more important in tilapia growing than in other species.

In this business you need to produce great volumes because tilapia is on its track to become important when feeding the masses, and Biofloc is the key to achieving this. Besides, you can have a small staff, as few people can take care of all ponds.

Infrastructure.

What infrastructure does Fish-Sul have?

SZ- There is 24 tanks of about 640 m2 and 3 m depth each. We use a 45º inyection aereator, which reaches up to 27 m, so we use two 2 hp aerators per tank. The aerators can last for about 4 years, and then some of the engines must be replaced.

One tank is intended for sex reversal.

There are two other tanks for broodstock and an 80x80 m tank for growing outside of the “hapa”, this one has a capacity of 1.000 m3. Within the “hapa” we raise fingerlings and juveniles.

AP- The farm was recently renewed. Today we have a system that is more resistant to wind; we will also add more tanks, so our production will grow to about 15 t per month.

Care and Maintenance.How old is the water you use?

AP- In some tanks, the water has been there for more than 4 years, it has been kept undrained and unrenewed, but we have to do constant monitoring, remove excess mud and replace the water that has evaporated.

How do you remove the excess mud and what can you do with it?

SZ- We installed a suction pump at the bottom of each tank, which removes some of the mud. The obtained product can be used for agriculture.

Prior to harvest, what are the basic parameters to be measured in order to maintain the Biofloc?AP- We normally measure the pH and salinity.

Is the water naturally brackish?

AP- No, we add the salt, to 3 parts per thousand. The original water was obtained from a 35 m depth well; it is 22º C even in winter. We add salt to enhance flavor and reduce illnesses; it also helps us regulate the ammonia. We could work with 5 or 6 parts per thousand, but the cost rises greatly. The technicians must add salt constantly because, although there is no refill, animals absorb part of the salt. It is very difficult to raise the salinity once a month when water has lost its balance, so you better add a little every day. Costs of salt for the whole farm are less than 1% of total production costs.

What do you do in case of a contingency? 

AP- At the back of the farm we have a 100x14x4 m tank with three times the capacity of the rest (3 million l), which works as a holding pond. It is used to refill the evaporated water and in an emergency can be used as a replenish source. Sometimes you need to empty a tank, clean it and stock it again, so you can decant everything in the holding pond. We barely use it, maybe once every 3 years. 

How can you empty the tanks on these occasions?

AP- The tank is emptied by gravity up to the middle, and then the rest is pumped.

The sludge remains in the bottom, so we must decide how much of it has to be removed. Then we pour the water back; the Biofloc may be diluted, but the mineral salts are still there.

Production

What feeds do you use for tilapia farming?

AP- For fingerlings up to 5 g, we use 56% protein feeds, then we transfer them to tanks where we provide a 42% protein feed. For fish from 50 g up, we provide 32% protein feeds.

What densities do you handle?AP- It all depends on the size of the fish. In the initial stages, we handle up to 25,000 fish per m3. At 700 g, the density is reduced to 12,000 fish per m3. When we reach the 1 kg mark, we low the density to about 10,000 organisms per m3.

Why not to buy more aerators instead of building more ponds in order to increase productivity?

AP- There’s a great risk in doing that. We once tried to stock the tanks with 30,000 fish per m3, but the system did not support the biomass. The fish was stuck in size at 4 weeks. Even with good oxygenation, we can maintain 25,000 fish, but when you get to that point, you must make a selection, separating the fish by size for a greater control.

How do you manage broodstock?

SZ- We have two breeding tanks. We do both incubation and hatched egg collection. Sometimes we get many fingerlings in breeding ponds, depending on how long the eggs stay there, the average time is at 10-12 days.

AP- The breeding tank is shallower as it provides a better protection from  the wind and it is cheaper.   Both tanks work as greenhouses for both broodstock and fingerlings.

Why do you produce fingerlings?

AP- We had to do it, because in the winter it’s difficult to get fingerlings for production. We started producing our own fingerlings and started selling the surplus. Depending on the amount of fingerlings sold, the price ranges from 80 to 90 reales (USD$ 47-53) per thousand fingerlings of 0.5 g.

Harvest and purification.

What is the harvesting process?

SZ- We do it with a sorting net. 4 people are needed; they must place the net and a sorting device at the end of the tank. Small fish pass through the sorter and the big ones remain in the net. When they get near the end of the tank, they remove the sorting net, then put another net and pull the fish to the end. Then there is another classifier, when small fish are returned to the water and big ones go to a special tank for depuration.

How do you handle depuration?

AP- We keep the fish in the depuration tank for a day, which is enough to eliminate any undesirable flavor from the meat. There is no need of depuration as Biofloc doesn’t give a specific flavor to the meat, but we prefer to do it, because a Biofloc tank could contain algae that would give a different flavor to the product.

Fillets.

How much of your production can be processed as fillets?

AP- Out of the monthly 6 t we produce, 35% is fillets, the rest is waste, we can’t exploit it because up-to-date, the processing plant isn’t ours and it would be very difficult to manage by-products. 

Human resources needed in a Biofloc System.How can you learn to correctly use Biofloc?

AP- Use of Biofloc is something you learn by reading specialized books be imitated or copied, as it depends heavily on field experience, it is a system that learns from trial and error and needs daily practice.

For how long do you train a person to manage a Biofloc system?

AP- I think they need an initial field training of about three to four weeks so they can understand the process.

Then they return to their plant, and the acquired knowledge will serve them only to know where to start. Then, when fish is ready, other training is needed, now in decision-making. The person will require support during the entire process.

You definitely need to find the right staff. It is a somewhat long process, because if you choose wrong, you won’t succeed. Moreover, technology transfer works more like a recipe than a manual, you can’t write everything in a book, because you would never end.

Final comments and conclusions.

Can you make a final comment for our readers?

AP- I cannot emphasize enough the importance of Biofloc systems in the success of aquaculture of species such as tilapia. This industry has a very promising future in Brazil, it is already a reality, and Biofloc has enabled us to face difficult times when the product was not known in the region.

The advantages of Biofloc are many and it is vital that farmers know these technologies so they can exploit the full potential of their farms.