Management of Euglenophytes Bloom in Fish Pond at Rajshahi, North-west Part of Bangladesh

Abstract

An attempt was made to study the management of euglenophytes bloom in fish ponds by application of duckweed and lime. The study was carried out for five months in twelve fish ponds at Rajshahi, Bangladesh under four treatments viz., T1 (the ponds with duckweed, Lemna sp.), T2 (The ponds with lime, CaO), T3 (The ponds with both duckweed and lime) and T4 (The ponds without duckweed and lime as control). The study ponds were stocked with Labeo rohita, Catla catla, Hypophthalmichthys molitrix, Puntius gonionotus and Cirrhina mrigala at 60 juveniles/dec. Water quality parameters, algal community and density, and growth performances of fish were monitored by using standard methods. The results showed that the application of duckweed and lime in the ponds had positive effects on water quality, euglenophytes density and fish growth. Better water quality, lower density of euglenophytes and higher growth of fish were recorded in T3 as compared to other treatments (P<0.05). The present study indicates that application of duckweed and lime in combination is better for management of euglenophytes bloom in fish pond.