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I need help with my final project protocol - (Dec/07/2010 )

I am doing a project for my final year of university, my project is about looking at the abundance of MRSA in environmental samples. I know the basics of the labwork, I need to plate sea water onto manitol salt agar then, I need to perform gram stains, catalase and coagulase tests then finally a resistance test for methicilin.But I have no idea what concentrations of sea water to use ( if I need to make concentrations of sea water at all ). I dont how to measure the bacteria whether I need to do a colony forming unit or could I use a spectrophotometer. I dont know how many plates to make or whether I need to use another broth for the media, I dont know how to exactally test for methicilin resistance as the lab assistant said to me that we are testing with oxicillin and we dont use rings of inhibition. Finally because I am not sure if I will get any quantitative data I dont know what statistical analysis I need to use, I was thinking maybe a t test but I dont know. If anyone could tell me the best protocol for these experiements I would be so greatfull.

-alias me-

Hola, Lot of questions, but to start with the methos(that i never have work with staphilococcus neither waters) I will take different amounts uf sea water, from 5ml to 2l (I haven┤t idea of the abundance) and I would filter with 0.22u with a prefilter for solid materials and bacteria were retained in the surface. Put the filter on an agar medium plate with the filtering side on the agar for any time and incubate at 37║C(┐3hrs?) Retire the filter and next day count colonies, with the colonies formed you can made replicas in different media to isolate the s.a colonies and make the ulterior biochemical test. Look any ultrafiltration catalogue or webs, were you will have information of water ultrafiltration and microbiological methods. Buene suerte