The time it will take fish fingerlings to reach table size (market size) depends on your feeding, housing and every other management procedures put in place. If properly managed, your fish should be ready for table after six months. Meanwhile this also depends on the weight you are targeting for your fish. If they are well fed, they should reach an average of 1kg within the 6months.
Though the growth of fish depends on the quality and quantity of the available food, environmental factors etc., there is a definite rate of growth for different fish species. Some fishes grow to very big size over the years while there are fishes as small as a few millimeters in size and reach their maximum size within few days or weeks.
Thus the growth is a genetic and hereditary factor. In the profession of aquaculture or fish farming, this factor is profitably used to produce fast growing fish progeny through hybridization and selective breeding.
So far as the traditional food fishes of Indian fresh waters, Catla grows faster than Rohu and Mrigal. It reaches sexual maturity when it is around 1.5 to 2 kg. in weight by the end of 2 to 3 years.
Rohu and Mrigal are relatively slow growers. Regarding the maximum size, it will be different for different species. Catla reaches even up to 40 to 45 kg, in weight. The fishes are long living animals naturally.
In the wild, most fish species continue to grow until they die. Their growth rate slows as they age, and is influenced by many factors (food, water temp, etc), so not all fish of the same species and age are the same size.
Some fish reach adult size within a year, and some take much longer. At the extreme end, the Greenland shark doesn’t reach sexual maturity until it’s (estimated to be) about 150 years old!
On average, most of the fish that we eat (salmon, cod, bass, flounder, etc.) reach sexual maturity and “adult size” between 2–5 years old, though they continue to grow at a slower rate after that until they die.
Catfish Farming (Fish Fingerlings): What it takes to succeed
The business of catfish farming is not difficult to engage yourself in if you have the resources to do so. Catfish farming involves growing catfish to table-size, marketing them and selling them at a good price. It is a viable business that many people have gone in and out of for various reasons. Some have succeeded at it and made handsome profit while others have failed and abandoned it altogether.
Nonetheless, more people want to get into the business of catfish farming in Nigeria and they want to get it right. They want to succeed at it and make profit and so I get regular emails and calls from such people on what they need to do to operate a viable catfish business in Nigeria. I will try and answer them in a simple way that has worked for me.
My advice is to start small. Start with growing say one thousand (1000) pieces of juvenile catfish to table size in 15 weeks and selling them. Here are tips on the basic things you need and how to go about it.
Half plot of land;
Constant supply of fresh water from well or borehole;
3 Ponds each of about 8 square metres in area. The ponds can be made of concrete, tarpaulin, or polyvinyl chloride (PVC);
Plastic containers and one square metre of net.
2) Good Breed of Juvenile catfish or Fish Fingerlings
What are fish fingerlings? Catfish aged 0 – 4 weeks.
What are juvenile catfish? Catfish aged 4 – 8 weeks.
What are the catfish species commonly grown? Clarias gariepinus, Heterobranchus bidorsalis, and hybrid of Clarias and Heterobranchus (Heteroclarias).
Which catfish breed is best for growing? All 3 mentioned above will do well if properly managed.
How do you know a good catfish breed? They are healthy and lively at the fish fingerlings stage.
3) Three – four months feeding budget
It is important to ensure that you have a reliable supply of feed for the duration you grow your catfish. As of October, 2016 you need about two hundred thousand naira (N200, 000) to feed 1000 pieces of catfish from juvenile to table size in 15 weeks. A bag holds 15kg of floating catfish feed.
4) Catfish farming activities
Feeding. Catfish are carnivorous animals. You feed the catfish 2 times daily in the mornings and evenings. You can feed 3 times daily too but be consistent with whichever number of times you choose to feed your catfish. When you feed the catfish spread the feed over the area of the pond so that every fish has a good chance of feeding well. Feed till satiation. Use quality feed. The cost per bag of quality feed might seem high but the aim is to grow the fish from juvenile to table size as quickly as possible in less than 16 weeks. In the long run feeding with quality feed saves time and money.
Change the catfish pond water regularly. Endeavour to change the water in the pond every 3 days. In the first month changing every 4 days will be okay.
Like human beings catfish grow at different rates. Sort the fish by size every 3 – 4 weeks and keep catfish of similar size in the same pond.
Catfish in the ponds should be spaced out. Overcrowding of catfish wastes feed and slows growth.
Favour the faster growing fish. Feed them well and prioritise their spacing. If you do it right they should hit table size in 10 – 12 weeks.
Sell your catfish as soon as they reach the marketable size you aim for. When you clear the faster growing fish you can space out the remaining fish to occupy the pond space vacated by the faster growing fish.
Catfish eat more feed as they grow older so the longer you keep them in the ponds when you can sell them at a good price the more costs you incur. A substantial cost of operating a catfish farm goes to buying their feed.
The profitability of your catfish farming activities depends on the effectiveness of your marketing. Your marketing should begin the day you decide to go into the business. You should keep abreast of:
The price people buy their catfish from sellers in the market.
The price sellers buy their catfish from the catfish farms.
How sellers buy their catfish from the catfish farms.
The cost of catfish feed.
The total costs of running your catfish farming business.
Records are very important to your business. Types of records you should keep are:
Purchase records: This includes the day you buy your fish fingerlings or juveniles, the quantity you buy, and the cost. You should also record the quantity of feed you buy, the days you buy them and the frequency with which you buy them. Also record the frequency with which you feed the catfish.
Financial records: You should record the costs of purchases you make as well as the value of sales you make. Record the money input to the business and the sources.
Customer Records: It is important that you know the people that buy from you and why they buy from you.
7) Know other fish farmers and farms around you, Let them know you too
Understanding the above steps, implementing them and being committed to the enterprise of growing, marketing and selling your catfish are key to running a viable farm.
When you master how to grow 1000 pieces of catfish to table size you will be better prepared to scale up the farm to grow 10, 000 or even 20, 000 catfish. That is when the real business begins.
Another step up the value chain of catfish farming in Nigeria for instance is having the capability to process and preserve your catfish. This will be the subject of another write-up.
Meanwhile, here are more amazing fish farming books to guide and assist you further: