Information relating to the effects of phytic acid (PA), an anti-nutritional factor (ANF) commonly found in plant protein ingredients, on the growth performance, feed conversion ratio (FCR), nutrient utilisation and whole proximate composition in the Malaysian giant freshwater prawn, Macrobrachium rosenbergii, is lacking. Replicate groups of M. rosenbergii (mean initial carapace length of 6.03 ± 0.30 mm; mean initial weight of 0.29 ± 0.02 g; n = 20 per replicate group) were fed graded levels of PA for 140 days. The basal diet, to which different levels of PA were added to obtain 0.26 (control), 6.48, 11.28, 16.53, 21.45 and 26.16 g PA kg-1, contained fishmeal, soy protein concentrate and wheat meal. Terminal sampling indicated that the growth performance, FCR and survival did not differ significantly between the groups receiving the different inclusions of PA within their diets. The apparent protein, lipid and energy utilisation responded negatively, decreasing significantly (p<0.05) with an increasing inclusion of PA, particularly within the groups of prawns fed diets with the highest inclusions of PA (i.e. 21.45–26.16 g PA kg-1). The whole body composition of protein (p<0.04), lipid (p<0.01) and gross energy (p<0.05) also decreased significantly with an increasing supplementation of PA, while the ash content significantly increased (p<0.01), most notably in the groups of prawns receiving the highest levels of dietary PA (26.16 g PA kg-1). In conclusion, inclusions of up to 11.28 g PA kg-1 appear safe but levels above this have negative impacts. The results show that PA had significant effects on the nutrient utilisation and body compositions (p<0.05) but not on growth performance and FCR (p>0.05) on the M. rosenbergii reared under the experimental conditions that were employed here

This study of biofilm column and multimedia filtration which consist of granular activated carbon (GAC)-biofilm configured up-flow fluidized expanded bed (UFEB) reactor and slow down-flow packed sand bed reactor. To empathize the effectiveness of the multimedia filter, the characteristics of the process in removing the recalcitrant organic compound were investigated. This multimedia filter was run in fluidized expanded bed with hydraulic retention time (HRT) ranged from 2-8 hours. The multimedia filter showed efficient performance with a removable of 75.49 % of iron (Fe 2 + ) and sulphate (SO 4 2-) 62.10 % was removed. More than 92.59 % of COD removal was achieved in this study. Besides that, this experiment also shows the good performance of ammonia (NH 4 + ), nitrate (NO 3 -) and nitrite (NO 2 -) removals, which ammonia removal is 45.16 %, nitrate removal range from 51.76 % to 82.98 % and nitrite removal up to 65.93 % respectively without replenishment of external carbon source. The biomass attached to the GAC was originated from the rainwater range between 177mgl -1 and 3886 mgl -1 .

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