Grey residue forming in toilets and sinks...

[Writer]

So for the last few weeks I've noticed a grey residue in the toilet and sink of the guest bathroom. I also noticed it in the master bathroom...

In all my months scrubbing toilets in this house I've never noticed this before. What could it be? Our pipes are a combination of PVC and copper piping. The only change to our plumbing we've had recently was our new sprinkler system... and yes, Virginia, we did install a backflow preventor. ;)

Should I contact our utility company? What in the world could this be? I hope we're not ingesting anything we shouldn't be. :eek:

[Suich]

1. If it was in my drinking water, I'd call, definitely.

:hi: