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"The present investigation was carried out in a semi-intensive brackishwater shrimp pond of 0.4 ha water spread area located near Tuticorin. The various physico-chemical and biological parameters of the pond were studied for a full crop spanning over 120 days. Water temperature was found to very between 26.3 and 32.0�C, salinity between 15.21 and 40.67 ppt and pH varied between 8.0 and 8.2. The secchi-disc reading ranged from 40.02 to 55.16 cm and the values of dissolved oxygen content was found to range between 3.52 and 6.58 ml/l. The chlorophyll 'a' content of the water fluctuated between 24.43 and 110.14 mgc/m3 and net primary production was 1.61 and 8.06 gc/m3/day. Particulate organic carbon content varied between 2.37 and 7.22mg/l. A maximum of (88.81 �g-at NH3 - -N/l) of ammonia was recorded on the 30th day followed by nitrite (87.96 �g-at NO2 - -N/l) on the 60th day and nitrate (92.86 �g-at NO3 - -N/l) on the 120th day, confirmed prevalence of nitrification in water column. Total nitrogen showed highly significant (P<0.01) positive correlation with the culture period. Phosphate - phoshorus was found to vary from 0.52 to 5.51 �g-at PO4 3 - - P/l. Sediment pH fluctuated between 7.8 and 8.0. Sedimentary organic carbon showed a highly significant (P<0.001) positive correlation with total sedimentary nitrogen. High rate of input and lower mineralization rate were found to be the major factors for the high organic matter present in the sediment. Apatite phosphorus content of the sediment was found to vary between 96.77 and 2806.45 �g-at P/g and it showed a highly significant (P<0.001) positive correlation with the total sedimentary phosphorus and culture period, was know to accumulate in the sediment. The elemental ratios of sediment viz. carbon to nitrogen, nitrogen to phosphorus and carbon and nitrogen to phosphorus were 174.12:1, 0.0195:1 and 2.776:0.01915:1 respectively. The various environmental factors analysed in the shrimp pond indicated a conductive rearing environment especially for the culture of white shrimp Penaeus indicus."