In a previous post regarding tilapia cultivation in tarpaulin ponds, it was stated that tarpaulin ponds were chosen based on narrow land and the cost of making it was not too expensive. The construction of tarpaulin ponds is usually not for long-term cultivation activities. In addition to tarpaulin ponds, concrete ponds can also be applied to minimal land. Judging from the capital spent, making a concrete pond is more expensive than a tarpaulin pool. However, the quality is much better compared to tarpaulin ponds. Concrete ponds can be used for a long time.

Concrete ponds have many advantages such as not easy to leak, easy to control and maintain. An irrigation system that can be designed as well as possible so that water circulation, pond drying, and maintenance are maximized. We can also arrange the design of the pond in such a way, we can make walls between ponds that have more than one pond considering that we can maximize the narrow land well.

There are many aspects that need to be considered and several things that we must prepare before starting fish farming in a concrete pond. Here we summarize how to cultivate fish in concrete ponds, especially tilapia cultivation.

1. Pond preparation

Preparation of a concrete pond includes the feasibility of a cultivation location which includes the following (Hidayat, 2018):

• It is recommended that the location of tilapia cultivation is at an altitude of 700-800 meters above sea level.
• Water sources come from rivers (springs or public waters).
• Pond water level >50 cm.
• Water flow >15 L/s.
• Soil type is clay (sand loam).
• Water brightness 0.4-1 m.
• Pond water temperature ranges from 25-300 °C
• DO water level is > 4 mg/L
• The pH of the water is 6.5-7.5.

2. Pond size

The size of the fish pond is determined by the number of seeds to be maintained, its size, and the area of land owned. For enlargement ponds, make the depth of the pond as high as 75-150 cm. For seed sizes of 3-5 cm, the stocking density of fish in one pond is 100-200 fish/m². And if the weight of the fish reaches 100 grams per head, the fish can be divided into several ponds.

3. Fish seed stocking

It is best to sow the seeds in the morning or evening. To avoid high stress levels. Acclimatize before stocking, which is to put a container containing fish seeds into the pond, then let it sit for 15 minutes. After the water temperature in the container and pond is the same, pour the seeds slowly and let the seeds come out by themselves (Jayadi, Asni, Scientific, & Rosada, 2021).

4. Feeding management

Feeding tilapia in concrete ponds is given as much as three percent (3%) feeding rate of the weight of the biomass with a frequency of three times a day. The feed given is in the form of pellets with a protein content of 14-16%. If the weight of the tilapia biomass that is kept is 60 kg and the feeding is three percent (3%) of the weight of the biomass. Then the calculation is as follows: 60 kg x 3% = 1.8 kg.

Then the daily feeding is 1.8 kg for three meals. With this kind of feeding management, the biomass weight is 504 kg with an average weight of 180 gram per head (Amalia, Amrullah, & Suriati, 2018). The method for calculating biomass is as follows (Center for Marine and Fisheries Education, 2012):

• Take a sample of some of the fish kept in the pond.
• Weigh the caught fish sample.
• Find the average weight of the sample.          
• Then calculate the biomass with the formula:

Feeding rate (%) used in fish farming is adjusted to the size of the fish. The smaller the size of the fish, the larger the feeding rate will be used. Feeding rate is also determined based on the type of fish being cultivated, the type of feed, the system and technology used in the aquaculture business, the purpose of the cultivation business (seeding or enlarging), as well as environmental conditions.

5. Harvesting

Tilapia harvesting can be done totally or periodically. For total harvesting, total drying of the pond can be carried out until the water level reaches 10 cm, then caught using a cane. Meanwhile, periodic harvesting is carried out without drying the pond, so that fish are caught using fine fishing nets that have previously been sprinkled with bran on top.

References:

Amalia, R., Amrullah, & Suriati. (2018). Manajemen pemberian pakan pada pembesaran ikan nila (Oreochromis niloticus). Prosiding Seminar Nasional Sinegritas Multidisiplin Ilmu Pengetahuan dan Teknologi, 252-257.

Hidayat, A. (2018). Potensi pembesaran ikan nila merah (Oreochromis sp.) Kolam air deras di daerah irigasi banjaran, Purwokerto, Jawa Tengah. Samakia: Jurnal Ilmu Perikanan, 12-17.

infoikan.com. (2016). Cara Membuat kolam ikan nila dari dasar. Retrieved Oktober 25, 2021, from https://www.infoikan.com/2016/10/cara-membuat-kolam-ikan-nila-dari-dasar.html#

Jayadi, Asni, A., Ilmiah, & Rosada, I. (2021). Pengembangan usaha kampus melalui inovasi teknologi budidaya ikan nila dengan sistem modular pada kolam terpal di Kabupaten Pangkajene Kepulauan. To Maega Jurnal Pengabdian Masyarakat, 196-207.

Pusat Pendidikan Kelautan dan Perikanan. (2012). Pembesaran ikan air tawar. Jakarta: Kementrian Kelautan dan Perikanan.