Melen Water and Seafood

General Information

Within the scope of the TÜBİTAK 124N067 Project, the second meeting with aquaculture production facilities was conducted with Mahmut Altıparmak, the owner of Melen Water and Seafood Company. Melen Water and Seafood is located in Sakarya Province, Türkiye. Established in 2010, the facility is a hatchery enterprise with a total area of 22,500 m² (including 2,000 m² of indoor space). The annual production capacity of the facility is 39 million fry. The hatchery produces Rainbow Trout fry, which can be supplied in different weights according to customer demand. The average production weight is 4–6 g, with a maximum of 10 g per fry. The production process utilizes tanks (for egg-larvae production) and concrete ponds (for fry production). A photo of the facility’s administrative building is presented in Figure 1.

 

Production Stages and Monitoring

Eggs purchased from foreign companies (Poland, Spain) are delivered to the facility. These eggs arrive at 230 °C/day in the sac stage. A trout fry hatches at 320 °C/day, meaning that if the water temperature remains constantly at 10 °C, it will hatch after 32 days. (Note: The maximum daily water temperature for eggs is 13 °C; higher temperatures harm the embryo. The ideal range is 7–11 °C. Hatcheries often accelerate or slow production at different temperatures. The egg producer provides customers with information such as the production temperature, the age of the broodstock, etc.)

The incoming eggs are placed in California-type trays and hatch as sac-fry after one week at 13 °C water temperature. Approximately 10 days later, once the yolk sac is absorbed, the fry becomes a free-swimming fish requiring feed. The entire process from sac-fry stage to active feeding takes about 17 days. Higher temperatures slightly accelerate this process. At this stage, the fry weighs on average 0.1–0.15 g. Feeding starts in tanks, with an initial feed size of 0.3 mm. A photo of the tanks used in production is presented in Figure 2.

 

 

After being fed with 0.3 mm feed for 4–5 days, the fry are fed with 0.5 mm feed for 7–10 days and then 0.8 mm feed for the next 10 days. Once the fish are able to consume 1 mm feed, they are transferred to outdoor concrete ponds.

In the facility, fish are initially raised in 85 ponds located on the lower side until they reach 1–2 g in weight, then moved to the ponds on the upper side. Juveniles raised in the concrete ponds for approximately 2 months reach a weight of 4–6 g and are shipped by trucks to contracted companies. The total process takes about 3.5 months. Figure 3 shows the concrete ponds located on the upper side of the facility, Figure 4 shows the concrete ponds on the lower side, and Figure 5 presents the empty ponds in the unused capacity area.

 

 

 

 

There are seasonal periods in production monitoring. This is because customers choose times when the temperature is suitable for placing fry into reservoirs or cage farms. The first batch of fry is shipped between October 15 and December 15. The second batch of fry is shipped between March 15 and April 15. Production at the facility is planned to align with these seasons, and large shipments are carried out during these periods.

Water Source

The water source is groundwater with a flow rate of 200 L/s. Aksu Stream feeds the groundwater source. No treatment is required for the water used in production. Water quality is not monitored regularly; however, previous analyses have shown that the values were well below the limits. While clean water content is preferred during the egg stage, it is stated that during the production stage, the groundwater source (GWS) having naturally occurring agricultural irrigation-related pollutants and a small amount of nitrogen content is not harmful to the fish.

Electricity Consumption

Energy is purchased externally (from SEDAŞ). An agricultural irrigation discounted tariff provided by the Ministry is used (15% discount). Energy consumption is 40 kW/hour per pump. The pumps used are energy-efficient.

Feeds

The feeds used at the facility are supplied from Skretting, a foreign company operating domestically. The feed is produced in France. Feed sizes used range from 0.3 mm to 0.5 mm, 0.8 mm, 1 mm, 1.2 mm, and 1.5 mm. Although the amount of feed used varies depending on the size of the fry, 1.5 mm feed is generally used. The feeds are delivered to the facility in 16 kg vacuum-sealed bags. For each kilogram of fry (approximately 200 fish), 500 g of fry feed is used. A photo of the feeds used at the facility is shown in Figure 6.

 

 

Chemical Use

During dry-out periods when the farm is drained for cleaning, sodium hypochlorite (bleach) is used in the concrete ponds to remove algal growth. In addition, disinfectants are applied to eliminate bacteria in case of viral contamination. Disinfectants are used a few times per year.

Waste

Solid waste generation at the facility is minimal because the fry have a very high digestion efficiency and the feeds used in production are highly digestible.

Water Quality

The facility is equipped with an oxygen meter and a pH meter for measuring water quality. These parameters are continuously monitored. A system is installed at the facility to adjust oxygen levels. The average measured pH is 7.4. Oxygen concentration can reach up to 20 mg/L, which is above saturation level. This approach allows for reduced water usage at the facility. The cost of oxygenation is more advantageous compared to water usage costs, and it is also highly important for preventing the overuse of the groundwater source.

Water from the alluvial plain of Aksu Stream infiltrates underground. The infiltration point is monitored, and the static level of the groundwater source (GWS) is maintained. Water level control is conducted to ensure pumps capture water at the highest possible level and to minimize energy consumption. Photos of the air tank and aeration system installed at the facility are presented in Figure 7 and Figure 8, respectively.

 

 

 

Symbiotic Relationship Between Mosquitoes, Algae, and Fish

In fish production ponds, algae mixed with fish feces form sediment, which serves as a food source for mosquito larvae. Mosquitoes lay their eggs in this nutrient-rich environment, and the larvae feed on the sediment, eventually developing into red worms. These larvae, being highly digestible, become a valuable food source for fish. Through this ecosystem established in production ponds, fish can obtain nutrients and minerals that are not provided by commercial feeds. Additionally, the small amount of algae formed on the pond surface helps prevent ultraviolet rays from the sun from causing burns on the fish skin. Furthermore, photosynthesis performed by algae produces oxygen, which is essential for the survival and growth of the fish.

Innovation

The facility engages in innovative practices. They emphasize that continuous development is achieved through close collaboration with university professors, monitoring global advancements, and leveraging professional experience as a source of learning and improvement.

Customers and Complaint Issues

Melen Water and Seafood supplies production to various companies across Türkiye. However, customer complaints have been reported regarding shipments and associated fry losses. The company demonstrates strong commitment to planning and fulfilling its contractual obligations, while also conducting R&D activities to ensure the supply of healthy stock. For instance, their R&D efforts on developing broodstock lines suitable for production serve as a clear example of this dedication.

Suppliers

Suppliers are the companies that provide feed, eggs, and facility operation materials.

Facility Workforce

The facility operates 24 hours a day. A total of five staff members are employed, including a night watchman and personnel responsible for daytime operational tasks. All employees are male, with an age distribution ranging from 20 to 50 years. Work is primarily conducted during daytime hours. The facility prioritizes hygiene and employs individuals who are knowledgeable about the operational processes. It has been noted that, at times, due to the comprehensive nature of the work, there are periods when recruiting additional staff can be challenging.

Local Community Development

Various initiatives have been carried out to support the development of the local community. For example, efforts have been made to establish an irrigation network from the stream source for local farmers in the surrounding villages where the production facility is located.

Recommendations

It was emphasized that aquaculture pond management requires expertise in various scientific fields such as biology and geology, and that having strong knowledge in these areas significantly contributes to the continuous development of facilities, given the importance of thoroughly understanding the cultured species.

Additionally, it was noted that there is a lack of expertise in the sector regarding water treatment, highlighting the need for further studies and capacity building in this area. Table 1 summarizes the key information about the Melen Water and Aquatic Products Facility.

Table 1. Summary information about the Melen water and aquatic products facility

 

GENERAL
Facility Area	Total Area: 22,500 m² | Indoor Area: 2,000 m²
Water Source	Groundwater fed by aquifers from Aksu Stream
Water Quality Parameters	Dissolved Oxygen: 20 mg/L, pH: 7.4
Capacity	39 million fry/year
ECONOMIC
Suppliers	Companies providing feed, eggs, and facility operation materials
SOCIAL
Number of Employees	5 in total (night watchman and daytime operational staff)
Age Distribution	20-50
Work Areas	Facility operation, night security
Work Schedule	24/7 continuous operation
ENVIRONMENTAL
Energy Consumption Areas	Pumps used in production, lighting, etc.
Chemical Use	Sodium hypochlorite for pond cleaning and disinfectants for bacterial control in case of viral contamination.
Generated Waste	Wastewater, solid wastes from fish excreta and uneaten feed.
INNOVATION
Ongoing Practices	Collaborations with university professors, monitoring global advancements, and observations of ecosystem dynamics within production processes.