Thanks for the suggestion but we did that in the first place...it was clean until the last sample.

Unfortunately because Scrappy is so small (chihuahuaXterrier) and he has arthritis in his hip, its rather hard to whip anything underneath him.

We actually went out and bought the flattest plastic container we could find to try and get it underneath him. And now he has become gun shy.

Ah well, looks like we tip it all out and try again (sigh)