Environment-friendly floating net cage culture research in Indonesia

Reservoirs and lakes are widely used for fisheries, both capture fisheries and aquaculture. Aquaculture fisheries that develop in reservoirs or lakes include floating net cages culture (FCC) and pen culture. Besides impacting the economy and employment opportunities, aquaculture activities through FCC can decrease water quality from uneaten feed and fish metabolism residue. For this reason, an environmentally friendly FCC is needed to reduce aquaculture waste. This paper reviews the development of ecologically friendly FCC research in Indonesia. Several studies on environmentally friendly FCC include double net FCC, bio-cages, carpel FCC, windowed, and triple layer FCC. Double net FCC still allows the remaining uneaten feed and feces to settle. Bio-cage research is in the innovation model stage and has no prototype or laboratory tests. Windowed FCC, made with a closed system and a few gaps for circulation, can accommodate aquaculture waste and not spread into the waters, but fish grow slower than other FCC. The loop bio-phytoremediation of FCC or Smart FCC has three layers that can accommodate waste, and the waste will be used for plants that function as filters and phytoremediators of waste. Smart FCC is an aquaponic system modified to be applied in reservoirs/lakes

Environment-friendly floating net cage culture research in Indonesia

Reservoirs and lakes are widely used for fisheries, both capture fisheries and aquaculture. Aquaculture fisheries that develop in reservoirs or lakes include floating net cages culture (FCC) and pen culture. Besides impacting the economy and employment opportunities, aquaculture activities through FCC can decrease water quality from uneaten feed and fish metabolism residue. For this reason, an environmentally friendly FCC is needed to reduce aquaculture waste. This paper reviews the development of ecologically friendly FCC research in Indonesia. Several studies on environmentally friendly FCC include double net FCC, bio-cages, carpel FCC, windowed, and triple layer FCC. Double net FCC still allows the remaining uneaten feed and feces to settle. Bio-cage research is in the innovation model stage and has no prototype or laboratory tests. Windowed FCC, made with a closed system and a few gaps for circulation, can accommodate aquaculture waste and not spread into the waters, but fish grow slower than other FCC. The loop bio-phytoremediation of FCC or Smart FCC has three layers that can accommodate waste, and the waste will be used for plants that function as filters and phytoremediators of waste. Smart FCC is an aquaponic system modified to be applied in reservoirs/lakes

Phytoremediation for nutrient removal in an environmentally friendly floating cage system: a field experiment

Aquaculture is one of the efforts to optimize the utilization of water bodies. Aquaculture using floating net cages is detrimental to water, namely causing pollution from uneaten feed and fish excretion. Water quality would be degraded due to eutrophication, oxygen depletion, and uncontrolled growth of algae and aquatic plants. High concentrations of nitrogen and phosphorus mainly trigger water quality degradation and eutrophication. To reduce the negative impact of aquaculture activities in floating net cages in reservoir/lake waters, an environmentally friendly cage technology that is low waste is needed. The technology offered is a loop bio-phytoremediation system equipped with floating net cages, a water management system with recirculation, and plants. The floating net cage used is a double net where the upper net consists of two nets and a bottom net. The upper net is used for rearing carp fish, and the bottom net for tilapia. The plants used as phytoremediation agents were water spinach and vetiver grass. Moreover, the physical filter used for processed water before recirculating to the waterbody in the FNC consists of sand, palm fiber, and limestone layers. The results showed that the effectiveness of nutrient removal on water spinach hydroponic (HRT=15 h), vetiver grass wetland (HRT=36 h), and physical filters (HRT=2,4 h) in reducing nitrate was 83%, 86%, and 67%, respectively; maximal reduction of the organic matter reached 94%, 96%, and 96%, respectively; as well as the highest reduction in total phosphorus was 78%, 89%, and 82%, respectively