>> Lynn wrote:
>> > R2A was on my list, What is Cled? We currently do a lot of VRBA plates
> > for coliforms but I was going to try a broth for MPN on the water
> > samples, esp ones with low counts.
> > Cheers Lynn
>> Hi...Years ago we worked with wastewater testing on our local duck farms.
> One of our tests was for post chlorinated returned water. We expected
> small numbers of colonies and the reference text we used had us using an
> endo broth test kit. The kit consisted of a grid marked filter and a pad
> of dehydrated endo broth meduim. The idea was to filter your sample (we
> used a gooch crucible and vacuum filter set up) . Sterile water was added
> to the medium pad in a ten ml petri dish. Then the filter was set on top
> of that and incubated.
> The endo broth is a dark magenta color but the E. coli would show up a
> brilliant metallic green. The grid on the filter made it very easy to
> count and do calculations.
>> We are now engaged in carcass contamination studies involving e.coli. We
> use 3M petrifilm for e coli counts. For this test, unlike the other, we
> do a titration of the carcass wash.
>> Hope this helps.
> International Duck (you heard right <G>) Research Lab
Hi Diane thanks for your info. I use the 3M petri film for e coli also
but only as an id for colonies growing on my VRBA's. I find it easy to
use but Im not too sure if it is approved for potable water testing.