Asian redtail catfish, Hemibagrus nemurus is one of the local species that have an economical values in Southeast Asia including Indonesia. The research aims to obtain the optimal of duckweed biomass as phytoremediation on survival, growth, stress response, and water quality dynamic of Asian redtail catfish culture. The different of duckweed, Lemna sp biomass as a treatments were as followed A) 0 gram (control); B) 20 gram; C) 40 gram; and D) 60 gram. Three replicates were performed for each treatment. 12 fiber thanks with size of 60 x 40 x 40cm were set up where each thank was stocking 50 fishes. The result showed that the Lemna sp biomass affect the survival, growth, biomass, and blood glucose (P<0.05). The absolute biomass of Lemna sp yield were also significantly different (P<0.05). Water quality dynamic during the culture such as nitrite, nitrate, total of ammonia, phosphate concentrations at the control (0 gram) was the highest compared to the others where the dissolved oxygen (DO), pH and temperature were relative constant. The Lemna sp biomass of 40 gram can be recommended as a phytoremediation for culturing seed in order to increasing productivity and keep the water quality in the optimal range.

Fentin acetate is used as a pesticide in rice fields to eradicate pests. Research with physiological factors approach is expected to increase the survival rate and growth performances of tilapia. The purpose of this study was to determine the impact of different concentrations of fentin acetate on the biological performance and hematological characteristics of tilapia (Oreochromis niloticus). The research used 16 rice fields with a 30 m2 each (6 x 5 m). The research design used a completely randomized design with four treatments and three replications: A. 0.00 g L−1, B. 0.375 g L−1, C. 0.75 g L−1 and D. 1.5 g L−1. The results showed that treatment C resulted in the best growth of tilapia. It was noted that absolute weight gain, daily growth rate and productivity were significantly different (P<0.05) with treatments A, B and D. The highest value in treatment C were 20.53 g (absolute weight gain), 5.43 (daily growth rate) and 501.58 g (productivity). The survival rate in treatments B and C were not significantly different (P>0.05) as well as treatments A and D. The concentration of molluscicide fentin acetate at a dose of 0.75 g/L affected the decrease in the hematological characteristics of tilapia.