Broodfish rearing and breeding facilities development: Broodfish rearing and breeding facilities were developed before starting the experiment, besides the faculty building of Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur. The mini hatchery has six cemented cisterns (5' × 3' × 4') for brood fish rearing, two (6' × 5' × 3') cisterns with bottom mud for hatchling rearing of indigenous climbing perch. A plastic tank (500L) was used for supplying water holding in the rooftop in a house was used as an incubator for spawning and hatching fish after modification. The upper side of the tank (6 inches) was cut and removed, and it was then open on the upper side. Inside the tank outlet, a short piece of pipe (with a diameter of 0.5-inches and a length of 15 inches) was horizontally set and came to the center of the tank and then using another short piece of pipe (15 inches) used vertically with the elbow. The outside outlet of the tank was also connected with another short piece of pipe having a height of 15 inches. Thus, the water level was maintained by lowering both the inside and outside vertical pipe upward and downward. The mouth of the inlet and outlet pipe was covered by a fine mesh size net so that the egg cannot come outside of the tank along with the water flow. The upper opening mouth side of the tank was also covered by a fine mesh size net so that fish can’t escape from the tank. The tank was then set under a horizontal water supply system by a short porous piece of pipe (36 inches) with the dead-end mouth. Thus, twelve plastic tanks were prepared and used for breeding in the present experiment. Digital electric balance was used for measuring fish weight. A plastic bowl, petri dish, and beaker were used to count the number of eggs, fertilization, and hatchling. Brood fish collection and rearing: Five hundred brood fish of native koi from each of the two populations Netrokona (Bandha beel, Mohonganj) and Sylhet (Murier haor, Golapganj) were collected in January 2017, and the fish were reared and kept in the cemented tank (5' × 3' × 4'), having a water height of around 3 feet. Approximately 120-150 fish were kept in each cemented tank, and the fishes were fed with a commercially available feed twice daily at 5% body weight. The broodfish were fed a VitE supplement with the feed. The excess amount of feed and excreta was cleaned every day, and the whole water of the tank was changed twice a week. Experimental design: The experiment was designed with four treatments T1, T2, T3, and T4 (treatments T1- Netrokona × Netrokona , T2-Sylhet × Sylhet , T3-Sylhet × Netrokona , T4-Netrokona × Sylhet ?) for two populations, and each treatment has three replications (R1, R2, and R3). Temperature and dissolved oxygen were recorded a similar (p>0.05) in all treatments throughout the research period. The average temperature and dissolved oxygen with standard deviation (SD) was 28.8±05 and 5.4±0.3, 29.3±05 and 5.1±0.3, 30.1±05 and 5.2±0.3, and 30.2.8±05 and 5.4±0.3, in T1, T2, T3, and T4, respectively. Broodfish response in captivity and breeding trial: Broodfish maturity was checked weekly since March 2017 to observe whether eggs and sperm come out after gentle pressure in the abdomen. Thus, the maturity check continued, and the first maturity response was found in the first week of April. One breeding trial, including broodfish selection, hormone injection, ovulation, incubation, fertilization, hatching, all steps took around two weeks. Thus, six breeding trials were done from April to June. The breeding response was found the best in the middle of this period. However, the best three breeding trials were used in the present experiment. The male and female fish weights varied from 27-51 g and 37-95 g. The average weight (g) of brood fishes used in different trails. In each treatment, three pairs of male and female fishes were used, and thus, in each trial, 72 fish were used in the four treatments (T1, T2, T3, and T4). Assessment of breeding parameters of A. testudineus: The total number of eggs and the number of fertilized eggs were calculated by the volumetric method after ovulation and fertilization in the 500L tank. At first, water containing fertilized eggs from 500L tank were taken in a 1 Liter biker and counted total eggs and fertilized eggs and recorded. This way, it counted ten times, and the average number was multiplied with the total volume of the water (average 50L) in the tank, and approximate total egg number and fertilized egg were estimated. However, fertilized eggs were transparent, while unfertilized eggs were opaque in appearance. The fertilization rate was determined by the following formula: Fertilization rate (%) = {(No. of fertilized eggs) / (Total no. eggs (fertilized and unfertilized)) x 100. The hatched number was counted in the same way mentioned above, and the hatching rate was determined by the following formula: Hatching rate (%) = {(No. of eggs hatched) / (Total No. of eggs) x 100. The survival number of spawns was recorded after 4, 7, 14 days after hatching following the method described above, and the survival rate was determined by the following formula: Survival rate (%) = {(No. of survived) / (Total no. eggs) x 100.Statistical analysis: The gathered data were summarized and scrutinized consciously before actual tabulation. After data entry, the data were analyzed by Statistics 10.0, and the results found in the experiment were subjected to statistical analysis, ANOVA (one way), that showed the significance (p<0.05) level of differences between treatments. Significant results (p<0.05) were further tested by the LSD multiple range test.