[macdonda]

Hi,

A colleague of mine was running some basic fecal counts; the filters were placed on m FC agar; after incubation, the controls were still transparent pink but all of the samples had transparent yellow 'patches' and 'streaks' through them - The water quality parameters that were tested (salinity, pH, ammonia etc...) were within normal ranges

The samples are deep-water river samples.  It looks like a chemical interference..

If anyone has experienced this, I'd appreciate some advice.

Thanks,
Dave