COMPENDIUM, IEEC-2023   ( ISBN : 978-81-967860-4-5 )
Theme-3: Bio-diversity and Resource Conservation, Livelihood and Food Security towards Sustainable Agri-food Systems

Water Quality and Growth of IMC, in an in-situ and Externally Produced Biofloc System

Sudhansu Shekhar Mahanand

College of Fisheries (CAU), Lembucherra, Tripura (West)


Biofloc technology has recently gained attention as a sustainable method to control water quality, with the added value of producing proteinaceous feed in- situ. The present study was conducted to compare the effects of in-situ produced biofloc and externally added biofloc on water quality and growth of IMC (Catla, Rohu & Mrigal) under different stocking densities Experiments were carried out in FRP tanks (1000 L each) for a period of 90 days. The experimental design included in-situ biofloc, externally added biofloc and control treatments conducted at three different stocking densities (STD) - 25, 50 and 75 no. fish m-2 of surface area of tank respectively with each experiment replicated thrice. IMC of individual average weight 15± 1.6 g was reared in all treatments. In in-situ biofloc treatment, low protein (20%) commercial fish feed was added initially. Further, organic carbon in the form of wheat flour was added daily to maintain the C:N ratio at 10 . 60% extra carbohydrate applied in a typical in-situ biofloc tank. In externally added biofloc treatment, 50% of fish feed and 50% wet floc was added. The biofloc was produced in a 25 m3 cemented tank using aquaculture effluent from a nearby carp culture pond and maintaining the best C:N ratio of 10. In control treatment, high protein (30%) commercial fish feed was added. The harvested weights of fish in all treatments with different STD were found to be significantly different among each other (p < 0.05). Fish survival was 100% in all the treatments. The FCR values in in-situ biofloc treatment and externally added biofloc treatment were less compared to control treatment. Frequency of water exchange was significantly less in externally added biofloc treatment compared to other treatments.

IEEC-2023 at RARI (SKNAU, Jobner), Jaipur, Rajasthan organised by Society of Extension Education, Agra, India