My secret of harvesting giant catfish

Domiciano Maingi and a few of his employees pose with a jumbo cat fish in his farm in Ruai, Nairobi PHOTO | RACHEL KIBUI

What you need to know:

  • Spread on the five acres are 18 fish ponds hosting mainly catfish, which Maingi has nicknamed jumbos because of their huge size.
  • The farmer keeps 60,000 fish in the ponds, most of which are catfish, while the others are tilapia.
  • The jumbos are for clients who want to make catfish fillet. He sells them at Sh500 per kilo, just like the other fish that he harvests at six months.

Nairobi is warm as we drive through Westlands, into the City Centre and then down to Thika Superhighway.

The previous day before making the trip last week, we had been informed that the weather is cold, but as we drove, we realised how tough the job of the weatherman is.

The weather has become extremely fickle, and many farmers are on the receiving end.

About 20km down the superhighway, we branch off to the Eastern bypass and then later onto Kangundo Road to Ruai, a sprawling suburb that has become a real estate hub.

Ruai is dry and dusty, perhaps why real estate is taking precedence in the area. We are in the fast-growing district to meet Domiciano Maingi, a fish farmer.

Dressed in a white shirt emblazoned with tilapia and catfish, one may not immediately notice how symbolic the shirt is to him, until they reach his Fish Paradise Farm.

Spread on the five acres are 18 fish ponds hosting mainly catfish, which Maingi has nicknamed jumbos because of their huge size.

The farmer keeps 60,000 fish in the ponds, most of which are catfish, while the others are tilapia.

I first met Maingi in Nakuru last month during a fish farmers’ forum organised by United Nations Industrial Development Organisation and the Aqua-cultural Association of Kenya.

CATFISH FILLET

It is at the forum that I learnt of his passion for fish farming, and the reason why he founded association in 2007, which was registered in 2008. He serves as the chairman of the organisation. At the farm, his employees fish from the water three jumbos at various stages of growth. The first weighs 15kg, the second 12kg and the third 10kg. The fish are a spectacle.

“You want to end up with such fish, or even one that weights over 50kg, then you must feed them well. It is all about feeding and you achieve the weight you desire in about 10 to 12 months,” says the farmer of the venture that he invested an average of Sh500,000 per pond.

The jumbos are for clients who want to make catfish fillet. He sells them at Sh500 per kilo, just like the other fish that he harvests at six months.

He harvests the other fish while weighing about 2kg for catfish and 300 to 400g for tilapia. The former is fast-maturing.

“Every pond always has at least two 50kg bags of cow manure floating inside. The manure helps to fertilise the ponds and boost the growth of algae, which is food for fish.”

Maingi makes his own fish feeds that comprise of fish meal (omena), cotton seed cake, wheat bran and Vitamin supplements. 

“I ensure the fish feeds contain 40 per cent proteins for the catfish and between 28 to 30 per cent of the same nutrient for the tilapia. Catfish are carnivorous, thus, if not well fed they can even eat the smaller fish.”

He has one full-time worker who feeds the fish twice a day at 11am and 3pm.

However, he adds the number of workers on special days such as during harvesting and when changing water from the ponds after every two months.

The farmer buys fingerlings from Kenya Fish Research Institute, Sagana and Jambo fish farms at Sh10 for tilapia and Sh15 each for catfish, ensuring that he ends up with high quality produce.

Domiciano Maingi points to his catfish ponds in his farm in Ruai, Nairobi PHOTO | RACHEL KIBUI

“There are many fish breeders around, who sell fingerlings for as low as Sh3 but they are not of good quality. It is the reason why I do not produce mine. I want to focus on rearing them to maturity, and leave breeding to those who know.”

His clients are diverse, ranging from processors, to hotels and general fish dealers, and he has maintained most of them since 2000 when he started the fish project.

He sells the fish once every two months, earning an average of Sh500,000.

“But I am working on having mature fish every eight months through synchronisation. I have learnt from experts that everyone who owns more than two ponds can actually produce fish monthly.”

Maingi gets water from a seasonal river which passes through his farm.

And when it cannot supply him with the precious commodity, he turns to his tanks.

“I have a reservoir in which I store rainwater which I use when I want to change water in the ponds.”

FISH ADDICT

Maingi recounts that his passion for fish started when he was five. Then, a Mr Ochieng, Maingi’s father’s workmate introduced him to fish.

“He gave me a piece of fish almost daily and told me to make it a regular diet so that I can end up a very intelligent person,” he recalls, adding, “I am until now, a fish addict. I do not like, I dearly love fish.”

His focus currently is the export market after the country was cleared to export fish to the European Union two weeks ago.

AAK, the government and other stakeholders had lobbied the EU to access the since 2012.

Maingi is among other fish farmers who have been trained through a European Union funded programme dubbed Standards Market Access Programme, which has been sharpening their skills on requirements for the export market.

As a volunteer and team leader at AAK, Maingi has been spearheading the ‘Eat More Fish’ campaigns mainly in Central Kenya, which aims at sensitising people of all cultures to embrace fish as rich, valid food.

Alex Akidiva, a research assistant at Egerton University, says farmers who want their fish to attain more weight must learn to feed them well and keep them in a good environment.

“Protein is the most key in making fish attain the desired weight.  Sources of protein include sunflower, soya, cotton seed cake and fish meal.”

He recommends 40 per cent protein content in catfish feeds and between 28-35 per cent for tilapia meals.

“The catfish have a higher protein requirement as they grow faster than tilapia and they are carnivorous.”

He adds that farmers can synchronise their ponds to ensure consistent production and, therefore, regular income.

“They should harvest fish that has matured and leave the rest to avoid unnecessary competition for food as fish do not necessarily grow at the same rate,” he says.and adds, “Farmers should ensure there have an activity in the ponds, from the fingerlings level to harvesting, at least monthly for higher income.”