A. BEGUM1, S. MONDAL2*, Z. FERDOUS3, M. A. ZAFAR4 and M. M. ALI 5
1=Aunguri Begum, Upazilla Fisheries Officer, Department of Fisheries, Dhaka, 2Subrata Mondal, Assistant Professor, Department of Fisheries & Marine Bioscience, Jessore University of Science & Technology, 3Zannatul Ferdous, Lecturer, Department of Aquaculture, Bangladesh Agricultural University, Mymensingh, 4Md. Abu Zafar, Lecture, Department of Aquaculture, Hajee Mohammad Danesh Science & Technology University, Dinajpur and 5Md. Mohsin Ali, Professor, Department of Aquaculture, Bangladesh Agricultural University, Mymensingh, Bangladesh.
*Corresponding author’s Email: subratajstu1975@gmail.com.
ABSTRACT
The study was conducted at Reliance Aqua Farm in Rahmatpur, sadar upazila, Mymensingh during July to November 2012 to monosex tilapia (Oreochromis niloticus) hatchery ponds with the view to evaluate it’s water quality parameters (physico-chemical) for successful production. The samples were collected from Reliance Aqua Farm at Rahmatpur in sadar upazila under Mymensingh district of Bangladesh. The experiment was consisted of three treatments having with two replicates. Six ponds were used for the experiment. The area of each pond was 18 decimal and water depth 1.2 m. Each pond was stocked with tilapia at the density of 200 fish per decimal. There were three treatments which are treatment 1 (T1), treatment 2 (T2) and treatment 3 (T3) respectively. Artificial feed was applied at 20% body weight at 1st month (up to 30 days) and reduced to 15% at 2nd month, 10% at 3rd month and 5% at the last month of the experiment. Water quality parameters such as water temperature, transparency, pH, dissolved oxygen, ammonia, nitrate and nitrite were measured at ten days interval. Parameters were measured by using thermometer, secchi disc, a portable multiparameter (HACH sensionTM 156) meter and HACH device (DR-4000), a direct reading spectrophotometer. It was found that most of the water quality parameters were within suitable range among three treatments. There were no significant differences in temperature among three treatments. But in T2, all the parameters were within desirable level. However, the highest DO was 7.29 mg/l found in T2. The ammonia content was 0.36 to 1.325 mg/l in T3 which was higher than T1 and T2. The higher ammonia content in T3 might be due to the decomposition of uneaten feed. The nitrate concentration was observed with null value (0.0 mg/l) in all the cases. From the present study, it could be said that excess feed (uneaten) which produce ammonia was the main problem for tilapia farming. The problem should be addressed from the view point of research and for better production. Finally, it was observed that among three treatments the highest production was recorded in T2 (40.19±513.53 kg/dec) compared to T1 (33.69±26.08 kg/dec) and T3 (36.14±189.56 kg/dec). The study revealed that the application of artificial feeding influenced the water quality parameters and production of fish in tilapia ponds.
Keywords: Monosex, Water quality, Production and Pond.