As a new microbiologist, I am currently working in a non-sterile production pharmaceutical factory where I take pure water samples from 13 points, fill 100 ml of pure water into 3 sample containers from each point, process them by membrane filtration and add them to TSA, SDA and MCA media to examine TAMC, TYMC and E.coli.

In the pharmacopoeia, only R2A agar is recommended for this work, but there are P.aeruginosa, S.aureus, E.coli and Bacillus subtilis bacteria other than TAMC and TYMC that I should look for in pure water. I use 39 petri and sample containers for 13 points and 3 samples each time, is this too much? I do not know what I am missing or unnecessary, I am still researching, what do you suggest me to do? Is there a method that you can give for sure and that works?