@ green | September-October , 2021

BY FATIHAH MANAF

Islam and Nik Mohd Azmi Nik Abdul Aziz , researchers at the Industrial Centre of Innovation in Sensor ( IC-I Sensor ) of SIRIM Berhad , shared with @ green the Underwater Fish Attraction LED Lamp ( UFAL ), a system developed by SIRIM under MOSTI Social Innovation ( MSI ) fund . It could be introduced to the coastal fishermen as a Fish Aggregating Device ( FAD ) to increase daily catch .

According to the researcher , UFAL utilises the green light spectrum to attract various plankton , fish , crustaceans , and other larger species in marine or freshwater water environments .

“ In the open sea , the green light spectrum is proven to be very effective in aggregating live organisms under the ocean water surface , which in turn provide abundant natural food for the pelagic fishes ,” said Noor Zalikha .

The SIRIM Industrial Innovation Model Fund ( SIIMF ) project in 2016 further improved the system based on the experiences in Langkawi , Yan and Pulau Aman .

She revealed that the field test at a floating fish farm in Kuala Muda , Kedah showed UFAL ’ s significant benefits in the aquacultural productivity through operational cost reduction and shorter harvesting cycle .

“ This technology could offer an alternative prospect in the marine aquaculture industry and help local SMEs to produce a reliable product to expand their business into new and niche markets . Based on the outcomes of field study , this promising technology could be the key to improve productivity in the marine aquaculture industry ,” said Noor Zalikha .

How UFAL system works Noor Zalikha said that the lightweight 30W output power LED lamp is made of conductive thermoplastic material for better heat dissipation in water . Depending on the availability of leading grid electricity , the system can be powered either by AC or DC power supply .

“ In an isolated area , the solar power system is used to supply 24V DC for operating the system which the on / off switching , and dimming can be controlled manually or automated . The automated controller that SIRIM has developed can be used to control four units of UFAL independently for auto-scheduling and brightness level setting to eliminate worker intervention requirements .

“ It is also installed with photocell sensor . If the sunlight level drops below the preset light intensity threshold , the system will be automatically on . However , the recommended operation hour for UFAL is throughout the night , normally from sunset to dawn where the lamp also provides surrounding ambient lighting for fish to see and hunt foods during their active hours .”

The researcher said UFAL body casing with nano-coating material makes the cleaning process for the system much more accessible and recommends the maintenance work to be carried out every month to prolong its lifetime .

Aside from having local design , engineering , and expertise in its system , Noor Zalikha said the lamp can easily be integrated with Internet of Things ( IoT ) technology platforms for smart systems . The maintenance is recommended once a month to prolong its lifetime .

Advantages of UFAL in the local aquaculture practices

“ Generally , the fish feed cost contributes 60 to 70 per cent of total operating cost for fish farming aquaculture ,” told Noor Zalikha .

In general , Nik Mohd Aziz said UFAL guides marine aquaculture entrepreneurs moving towards modern and sustainable farming , improves harvesting productivity , reduces operating cost and helps entrepreneurs to meet local and foreign demands market .

He shared that the advantages of UFAL in local aquaculture could be observed from its application at a fish cage farm in the brackish water river at Kuala Muda , Kedah .

“ After 10 months of data collection for performance monitoring , the benefits can be observed from the differences in physical and growth rate of sea bass and grouper cultured between the control and under test cages ,” said Nik Mohd Aziz

“ Under UFAL night green lighting , the growth of fish has been accelerated by 30 to 40 per cent , which indirectly shortens the harvesting cycle by around 20 per cent . For example , previously , it took at least 12 months for grouper to reach a market size of one kilogramme , whereas , with the UFAL application , the same batch of grouper reached the same weight within 10 months .”

He highlighted the result reduced the

Nik Mohd Azmi Nik Abdul Aziz

operation cost by 30 to 40 per cent on the feed cost per cycle .

“ However , the duration of the harvesting cycle is very much depending on the nature of the environment , especially the natural food availability in surrounding water of the aquaculture sites ,” he explained , adding that the application also led to a lower mortality rate of fish larvae .

He noted that UFAL had attracted various marine fish species , with the abundance of phytoplankton and zooplankton species surrounding the lamp . Nik Mohd Aziz highlighted that at least 15 higher density population phytoplankton species had been identified under UFAL exposure , compared to only 11 species in non-UFAL cages . This scenario has then provided abundant natural food for cultured fish .

“ Some species such as Limnothrix and Euglena prefer a non-UFAL condition due to their ability to grow and obtain energy under low light environments . As the phytoplankton are the food sources for zooplankton , its higher density from various species diversity has a direct impact on the higher density of zooplankton population around the lamp .”

Success story in the field trial at Kuala Muda

According to Noor Zalikha , the UFAL application field test in the brackish water river of Kuala Muda was conducted for 12 months , starting from November 2017 .

“ This cultivation began with 3-inch larval size , where a continuous monthly monitoring and data collection on the weight , health , survivability , physical appearances , and parasite attacks was conducted and recorded . The fish in each cage were fed twice a day ( morning & evening ), either with commercial pellet or trash fish .

“ The feeding management practise is per the recommended Feed Conversion Ratio ( FCR ), which is generally accepted between 0.7 to 1.5 for optimum growth . FCR is a tool for farmers to calculate the amount of feed necessary to grow a kilogramme of fish .

“ After completing one harvesting cycle ( 12 months ), the finding data has been able to convince the site owner on the benefits of UFAL application in his operation .

“ By integrating the technology of UFAL with a suitable standard operating procedure ( SOP ) productivity in aquaculture can be significantly increased by reducing the feeding cost , harvesting cycle , and dependency on manual labour for cultivating a uniform growth of fish ,” explained Noor Zalikha .

In 2021 , SIRIM Industrial Research launched the marketing and sales plan for UFAL commercialisation . It can be purchased directly from the ICI in Sensor , SIRIM . SIRIM will provide the guidelines for installation and operation for individual units . Still , for big-scale commercial projects , a consultation with SIRIM for a total technology solution is highly recommended . — @ green