Experiment 1: We will collect surface water from 3 IDM invaded (Whitmore, Cedar, Bruin) and 3 IDM-free (Bishop, North, Woodland) inland lakes. Water collected from these lakes will be filtered using a 153 μm Nitex mesh to remove debris and large zooplankton. One L filtered water from each lake will be transferred into dialysis bags in triplicates. All bags (6x3), which allow for nutrients but not biota to pass through, will be placed in a cattle tank filled with water from Douglas lake. Each dialysis bag will be non-destructively sampled, every 3 hours for 24 hours, by removing 1 ml water for FCM analysis. The goal of this experiment is to determine the compositional and phenotypic changes occurring by changing environmental conditions to Douglas lake water and select the optimal equilibration time before addition of IDM in experiment 2. Experiment 2: We will follow the same protocol as above to process water from each lake and transfer to dialysis bags into an Douglas lake water containing cattle tank. This time, however, we will set up 54 dialysis bags and let the bacterial communities equilibrate based on experiment 1 results. Two IDMs will be added to 3 dialysis bags from each lake. Response of bacterial communities to IDM will be tracked using FCM and 16S rRNA gene sequencing. 3X6 IDM free samples and all 6X6 remaining samples will be destructively sampled for 16S rRNA gene at the beginning and end of the experiment (set at 3.5 hours based on previous experiments), respectively. Before the samples are destructively sampled, 1 ml will be preserved for FCM analysis.