Selecting Fish Combination of Polyculture to Reduce Periphyton Abundance in Floating Net Cage in Cirata Reservoir, West Java, Indonesia

Abstract

Being a considerable potential area for aquaculture activities in the form of floating net cage, reservoir has taken on issues due to its characteristics as a common property with an open access. The problems have led to the vast growing and uncontrolled number of the net cages; one of which occurs in Cirata Reservoir. The objective of this research was to find the best combination of fishes in polyculture at Floating net cage in order to reduce periphyton abundance and to increase aquaculture productivity in Cirata Reservoir. The research has been conducted from February to March 2015. The research method used completely randomized design with three treatments and three replications. The treatments consist of fish combination of tilapia with silver barb, carp with silver barb, and black pacu with silver barb which were cultured for five weeks in floating net cage size (1 x 1 x 1) m3. The individual fish weight were approximately 10 g for tilapia, carp and silver barb, and approximately 4 g for black pacu. stocking density were 80 fishes per unit cage (40 fishes for each species) . The combination of black pacu and silver barb produced highest productivity of 459.77 gr / m3 or 82 % during five weeks. Meanwhile, combination of carp and silver barb gave lowest periphyton abundance of 28 345 cells / cm2. It can be concluded that black pacu and silver barb is the best combination due to growth rate and aquaculture productivity but not in periphyton abundance.Keywords: Polyculture, Cirata reservoir, Cageculture.