A Flow cytometric bacterial enumeration from fathead minnow from no water exchange biofloc system

This study was designed to use flow cytometry as a tool to document microbial communities in a zero water exchange super-intensive system from fathead minnows stocked at different densities. Biofloc growth was induced in no water exchange super-intensive system by periodic additions of a carbon source (glucose) to maintain a C: N ratio of 12:1. Microbial communities were distinguished at the gram-stain level using flow cytometric fluorescent activated cell sorter (FACS) methods. Differentiation between all other bacterial populations between 1~20 mm was based upon auto fluorescence and forward scatter (a size indicative light parameter) using FACS. Different types of stains were used to differentiate gram-positive and gram-negative bacterial populations using different stains. Samples were prepared for enumeration of bacteria by flow cytometry. Data are currently being analyzed and results will be presented.