How do I know how to raise catfish fries to fingerlings in Nigeria? How do you grow catfish fingerlings? How do you make catfish fry grow faster? What should I feed catfish fry? How long does it take a catfish fingerling to mature? How do you take care of fingerlings? What food makes fish grow faster? Why is my catfish not growing? What is the best feed for catfish fingerlings? What is the difference between fingerlings and juveniles? How old is a fingerling? What size are fingerlings? How many times do you feed fingerlings? How do I stop my fingerlings from dying? What are the stages of catfish growth? How much are catfish fingerlings? How long does it take fry to grow to fingerlings? Where is the fry raised to fingerlings?
Let’s now see how to raise catfish fries to fingerlings.
Handling Of Fries To Fingerlings And Water Control In The Hatchery Incubator
Pass in water into the incubator using a tiny hose of a tap at a rate of one litre per minute and also adjust the water outlet to exit the water at the same rate.
The water inlet hose or tap should be placed opposite the outlet pipe. This process of water inlet and outlet should continue throughout the incubator period.
Make sure you cover most part of the incubator with tarpaulin or wooden boards while the remaining part where the water inlet hose is located should be covered with a mosquito net to prevent predators from entering or tampering with the pond.
This will also create a conducive atmosphere for proper hatching and nurturing of the larvae to fries.
Handling Of The Larvae/Fries In The Hatchery/Incubation Pond
Once the incubation and the hatchery process are completed – usually 24 hours after spraying – allow enough time for most if not all eggs to hatch completely.
Note that the waiting period shouldn’t exceed 6 hours, after the initial 24 hours, especially during the dry season or when and where the temperature is high.
Remove the mop and increase the flow of water into the incubation and the un-hatched eggs.
The un-hatched eggs are whitish in colour. To prevent them from polluting the water, carefully siphon them out, using the small 4mm water hose.
Direct the mouth of the hose at the suspended or settled un-hatched eggs using your left hand and then with a broom in your hand, pick up the eggs so that the force of the water will suck them up and flush them through the hose out of the pond.
By applying this method you will avoid flushing out the fries with the un-hatched eggs. Alternatively, increase the water inflow and outflow so as to reduce water pollution. In this case, you don’t need to siphon the un-hatched eggs until 6 to 10 days later.
After this, always examine the pond water to ensure that it is neat. Also, ensure that the water inflow and outflow systems are functioning effectively.
In addition, the newly hatched larvae should not be fed until 48 to 72 hours after hatching is completed.
This is to allow each of the larvae to absorb its yolk sac which will also serve as its food for the initial 48 hours after hatching.
Meanwhile, the newly hatched larvae changes to fries from the third day after hatching and begins to feed.
Feeding The Newly Hatched Catfish Larvae
Start feeding them from the expiration of the 48 hours which was given to allow newly hatched larvae to absorb their yolk sac this means that they have to feed on the third day.
Start with boiled eggs yolk. Feed them with a little quantity of this for a day.
Thereafter, feed them with zooplankton (daphnia or artemia) brine shrimp and continue with either of these for the next 2 days before transferring them on the fourth day – counting from the day when the hatching was completed – to a larger nursery pond.
Boil the egg until it’s hard. Peel off the whitish shell, remove the yolk, crush it and mix with good water until it becomes milky, then use a teaspoon to put a drop each at the four corners of the hatchery/incubation pond where the fries are gathered.
You’ll easily notice them, when gathered they look like a handful – or less – of sand heaped on a spot and/or partially scattered.
In the case of zooplankton (daphnia) or artenia, use the fish fry net made from muslin material (a fine texture like women’s head tie) to scoop the zooplankton or artemia and put it in the pond water and the fish will immediately feed on them.
You do not need to put this feed in a particular spot because it is a live feed and thus can swim and will not pollute the water. A little quantity of this will be okay. Feed them between 2 to 3 times daily.
Preparation For The Nursery (Fingerlings) Pond For The Fish Fries Transferred From The Incubator
- Wooden board or synthetic polythene or tarpaulin
- Plastic water tank
- Two water filters made with white and coloured mosquito net, thread and one-quarter inch perforated plastic pipe
Two days before the transfer of the fries from the hatchery pond to the nursery pond, the nursery pond should be washed thoroughly, using the filter made with a white mosquito net to block the water exit pipe. After that, pump fresh water into it.
On the day of transfer, put zooplankton or artemia into the pond water to serve as their first meal once they get into the pond.
The water level of the nursery pond at this stage must be up to 10 inches. This has to be increased gradually as the catfish (fries) grow bigger.
Water Control And Management In The Nursery Pond
Do not allow the water to be polluted, smelly or deoxygenated. Once you notice that the fish always stay on top of the water, check for mucus or dregs that may have settled at the base of the pond.
If they are there reduce the water in the pond by 70% of the original volume by adjusting the water discharge pipe downward and siphoning them with half on a one-inch water hose.
As soon as you are through, refill the pond to the former water level with fresh water. This has to be done regularly.
Note that the water must be running 24 hours continuously for the initial 7 to 10 days of the transfer.
Thereafter, it could be run and stopped intermittently every 6 hours as long as the fish remains in the pond.
Furthermore, the water has to be inspected to ensure that it is very clean and clear always. Besides, the fish also has to have a black colour all through the period of monitoring in the nursery pond.
Handling Of The Fingerlings In The Nursery Pond
A week after transferring the fries into the nursery pond, the filter used in blocking the water exit pipe has to be changed to the one made with coloured mosquito net – green or blue – for ease of flow of water particularly after eight days of the transfer.
On a regular basis, sort out the shooters (faster-growing) fingerlings to avoid cannibalism and keep them in a different tank or pond filled with water and take good care of them as well.
Finally, always cover your pond day and night with polythene, tarpaulin or wooden board to shade it and also protect it from direct sunlight, rain and predators.
Feeding The Fingerlings
Types of feeds:
- Daphnia (zooplankton)
- Artemia (brine shrimps)
- Egg (boiled yolk), (raw shake yolk and albumen – the white) as binder
- Fish meal
- Mosquito or other insect’s larvae – after 12 to 14 days of the transfer
- Nestlé’s nutrient
- Guaranteed feed concentrates – after 12 to 14 days of the transfer
Your fish have to be fed between 5 to 8 times daily and make sure they consume all the feed you give them at each feeding.
Feed the fish fries well and according to instructions from the day of transfer with all these feedstocks. Feed them mosquito or insect larvae, Moi Moi, as well as the granulated feed concentrates from the 12th or 14th day of transfer.
The feeding strategy is as follows:
Feed them with the daphnia (zooplankton) but place them directly in the pond, especially in the four corners. You can get the daphnia in gutters and stagnant pools of water in your neighbourhood.
As for the artemia (brine shrimps), you need to first hatch it by putting between 4 and 8 heaped tablespoonfuls of artemia cyst into a half bucket of salt solution (you can get this by using seawater or putting 4 heaped tablespoonfuls of industrial (coarse non-industrial) salt into a half bucket of water and place the plastic bucket of water in the sun using a small air pump (the type used in an aquarium) plugged t electricity to make the water to be aerated by bubbling it.
They will hatch into tiny life shrimps from 16 to 24 hours.
Boil the egg until it’s hard, peel off the eggshell, remove the yolk, crush it and mix with clean water until it becomes milky, use a teaspoon to put a drop each at the four ends of the hatchery/incubation pond and where the fries are gathered while feeding them with the egg yolk be very careful not to give them too much of it because it easily pollutes water, which isn’t good.
Feed them with 65% or 72% fish meal, using a teaspoon. Drop a half teaspoon on each corner of the pond and where the fish are gathered. Feed them with the 65% or 75% fish meal once a while because it easily pollutes water too and that’s not good for the fish.
Feed them with the mosquito or other insect’s larva after 12 or 14 days of the transfer. Put them directly in the pond, especially the four corners.
Feed them with the nutrient using a teaspoon drop, a half teaspoon gradually on each corner of the pond and where the fish are gathered. Feed them with the nutrient once in a while especially the first 4 to 10 days of hatching because it can pollute the water too.
Feed them with granulated feed concentrates
Every one or two hours after feeding the fries or fingerling with either egg or any of the concentrate formulations, make sure you flush the pond for at least 30 minutes by running water in and out of the pond.
To do this, open the water inlet and outlet simultaneously. This will help to reduce the pollution effect of the food given to the fish.
That explains how to raise catfish fries to fingerlings here in Nigeria. I described how to set up a catfish hatchery in Nigeria in my last article, in my next series, I shall be given you more insights into HARVEST AND POSTHARVEST OPERATION OF FINGERLINGS AND JUVENILES. If you need any help with the series so far don’t hesitate to contact us, we’ll be delighted to hear from you.