The number of microbial cells per mL from marine environments has been quoted as 1 x 10^6 cells. However water sampled from a marine coastal environmnet (popular beach, downstrean from a waste treatmnet plant) was found to only have 1 x 10^4 total microbial cells, when visualised using a microscope and epifluorescence stain, 2 orders of magnitude less than expected. Is this purely natural variance, or could perhaps the filter membrane in which the sample was vacuumed through (with a pore size of 0.2 micrometres) allowed some particlarly small microbial cells to escape, to account for this difference. Also of note, as this was along a beach, the sample is believed to have been higher in nutrients and sediment than typical marine surface water samples.