What you need to set up a fish farm

Aquaculture can be broadly classified into commercial, domestic or small backyard ponds.

For large commercial production system, at the onset it is made to set up an economically viable purpose-built facility designed to exactly and efficiently meet the desired production output/target market from the beginning.

You will get equipment such as oxygen generators, cyclone filters, drum filters, an ion exchange and electro-chemical regeneration system for removing ammonia.

You will also find computerised controllers and testing equipment that are developed specifically for industrial-sized aquaculture.

At such set up you also expect highly specialised professional management and systems and a team of workers.

For small backyard ponds, the equipment used includes air stones, air tubes, filter pads, or bio balls. And the whole thing can be managed loosely in a domestic set up by one person part-time.

“There must be money for the running cost. This is to cover items such as feeds, and any contingencies like treatment and transport, which you might spend up to the maturity of fish ready for the market,” explains Charles Mulamata, the chairman Africa Aquaponics Association. “No matter what you go with, there is need for determination, dedication, hard work and love for the job so as to benefit from the enterprise.”

Planning
Then there is need to prepare a business plan. “You must determine how much money you will need for quality fish feeds and where to get it from,” Mulamata adds.

“Go to the fish market near you to find out what type and the size of fish on demand and at how much for a particular size. Find out what permits you need to keep fish in that size pond in your area.”

Feeding
There are several fish feeds manufacturers and importers. Feeds in farming contribute 60 to 70 per cent of costs, so care should be taken in picking the right high quality reasonably priced feeds.

When the feeds are available, there must be optimal use so there is no wastage. “Make sure the fish eat it as soon as it is put in the water. Keep the stock safe from vermins and rodents and it should be dry to avoid mold,” he points out.

Work out the right quantity to feed your fish as it grows. Get a feed manufactures chart from the source of feed for a daily feeds programme.

Take out a random sample of your fish and determine their weight, try to find out how old they are. Match this with the feed chart and start a proper program.
What type of management you need to have in place? What do you have to do daily for feeding, cleaning, and determining if your fish is okay? Work out schedules, daily feed, weight tables, and other needed records for proper management.

NOTE
The water may have toxins, which can harm the fish.
Have water testing equipment available and monitor the levels regularly. Slowly changing parameters will not affect the fish until it reaches dangerous levels but quickly changing parameters can immediately affect fish health. Some parameters include Ammonia, Nitrite, Nitrate, pH, dissolved oxygen and temperature. You can also test for chlorine (if you use city tap water), alkalinity, hardness, carbon dioxide.

Some facts about farmed fish
Farmed fish has five basic needs to stay healthy and thrive to a fast growth including clean water, dissolved oxygen, food, light and room to swim.
• It is better to understand these basic needs and making sure that they are provided to the fish the faster your fish will grow to a good market crop for harvest and you will enjoy fish farming.
• Work out a regular fish sampling programme, weigh them to determine their size increase, grade them and try to match them with the feed chart.
• Continue with the programme and closely run according to the feed chart monitoring the weight gain and general health condition of the fish.
• From the hatchery, fish goes to grow out. Ideally at this stage, fish should be 10-40 grammes of adjusted body weight (ABW). This is the fingerling stage.

Settling in
Fish transported from the hatchery is introduced to the pond, tank or cage slowly after equalising temperature of the transporting container with the stocking facility. Take 24 hours to feed your fish after stocking.
• But since the fish is already in the pond, this must have been done by the person who introduces the fish in the pond.
• Water in which you introduce the fish should be clean.
• The temperature should be the same as what your tilapia are already accustomed.
• Use rain water or well water. Never tap water from the national grid because it not good, it usually has chlorine which is not favourable for fish.
Rearing, or grow-out: You want to raise your tilapia fish to harvest size economically, quickly and of good health to be attractive to the market and enable you to post a profit.
To do this, you must feed the fish well, test, weigh and sort the fish in different stages so that fish of same size is kept together.

Determining the feeds

Tilapia, a warm water fish, thrives on the following factors, water quality, temperature, oxygen, exercise and feeding rates. It is an avid eater if conditions are good. You can feed four to five times a day especially for the young fish you can go up to six times a day. This is because tilapia digestive system runs on a two to three hour schedule.

Reading the chart
Feed charts from feeds manufactures are the best guide as to how much to feed. Therefore feed can be calculated from such charts as follows:

An example of 200 fish, assume that they weigh 35 grammes each. Your tank will have 7,000 grammes of fish to be fed. From the chart, you can see that 35-gramme fish should be fed about four to seven per cent of their body weight per day.

We will take 5.5 per cent for this example because the 35-gramme fish are in the middle of the weight range on the chart.

Growth rate
The 5.5 per cent of the 7,000 grammes of fish we have is 385 grammes of food. Now split the 385 grammes of food in four feedings per day of 96.25 grammes each.
It is advisable to check fish weight on a weekly basis. Do this calculation each time you check and find the fish has registered growth and increase the feed amount accordingly. Also calculate the new fish weight by taking the weight of food you have fed in one week multiply by 0.75. In our example, this would be 385 grammes by seven days, which is 2,695. Take 75 per cent of this, 2,021.25 grams (the 75 per cent allows for the food conversion rate for tilapia).

Round this to 2,000 grammes. Then add the 2,000 grammes to the original weight of the fish at the start of last week 7,000 + 2,000 = 9,000 grammes.

Checking operations
This will be the new total weight of the fish in the tank. Now you should have 200 fish totaling close to 9,000 grammes, at 45 grammes per fish. Look this up in the chart and calculate the new feeding rate for this week. We will say 4.5 per cent of 9,000 grammes is 405 grammes per day.

The feed chart should be got from the manufacturer; the feeding rates are only a guide to use in determining if your system is operating correctly. But at all times seek professional help if things go wrong.

First thing to do is to stop feeding and determine the problem because the fish can go without feeds for about a week. So do not worry if fish is not fed for a day or two.

Check the water quality as the first step. Watch closely to be sure all food is eaten at each feeding. It can take several weeks for a clean tank and filter to work properly.