A small volume bioassay to assess bacterial/phytoplankton co-culture using WATER-Pulse-Amplitude-Modulated (WATER-PAM) fluorometry.

Conventional methods for experimental manipulation of microalgae have employed large volumes of culture (20 ml to 5 L), so that the culture can be subsampled throughout the experiment1-7. Subsampling of large volumes can be problematic for several reasons: 1) it causes variation in the total volume and the surface area:volume ratio of the culture during the experiment; 2) pseudo-replication (i.e.