Brewery waste (brewer's grains) was used at four different levels (10%, 20%, 30% and 40% w/w) replacing rice bran in fish diet under a semi-intensive culture system and its impact on the growth of catla, Catla catla; rohu, Labeo rohita and mrigal, Cirrhina mrigala, was studied. Growth in terms of body weight gain was maximum in C. catla and L. rohita fed on a diet containing 30% brewery waste in the feed, whereas C. mrigala, fed on a diet containing brewery waste at the above mentioned levels showed poorer growth than the control. A better growth performance was attributed to better absorption and utilization ability. (C) 2003 Elsevier Ltd. All rights reserved.