eng Enviro Research Publishers Current Agriculture Research Journal 2347-4688 2321-9971 2017-06-20 5 1 66 73 2255 article B. P. Bhoye 1 B. R. Chavan 1 V. R. Sadavarte 1 H. B. Dhamagaye 1 M. T. Kamble 2 B. T. Sawant 1 Faculty of Fishery Science, (Dr. B.S. Konkan Agricultural University), Ratnagiri, M.S., India. AARM, SERD, Asian Institute of Technology, Pathumthani, Thailand. The present study on the effect of green water system with harvested rain water on growth performance of freshwater fish Catla catla. Spawn of Catla with an initial length 5.50±0.04 mm and weight 10.99±0.30 mg were stocked at the rate of 6, 8, 10 and 12 no.l^-1 in cement tanks (2x1x1m). The green water system containing live phytoplankton viz., Chlorophyta, Cyanophyta and zooplankton viz., Rotifera, Cladocera, Copepoda and Protozoa were was used. The results of the study indicated that the maximum average length gain was (357.89±3.08%), weight gain (779.53±18.03%), specific growth rate (5.56±0.08%) and survival (45.20±0.13%) and were recorded significantly (P<0.05) at stocking density of 6 spawn l^-1 as compared to the other stocking densities. The growth of spawn to fry was observed to decrease with increase in the stocking density. Observations on the water quality revealed that the dissolved oxygen value decreased with an increased stocking density. Whereas, the value of ammonia-nitrogen, nitrite-nitrogen, and nitrate-nitrogen increased with the increase in the stocking density. The study showed that better growth and survival of Catla catla spawn to fry stage with stocking density of 6 spawn l^-1 reared for a period of16 days in cement tank.  The overall results of this study indicated that green water system with harvested rain water has a potential for rearing fish seeds. http://www.agriculturejournal.org/volume5number1/rearing-of-freshwater-fish-catla-catla-hamilton-1822-spawn-to-fry-in-green-water-system-with-harvested-rain-water-in-cement-tanks/ Catla Catla; Spawn; Fry; Aquaculture; Chlorophyta; Rotifera; Rain Water; Cement Tank