ne to the kitchen in the middle of the night to find a slug in my sink. There was another climbing up the sink unit door and another on the draining board heading for the sink so they may not be coming up through the plughole..
After a few weeks of seeing the shiny trails across my kitchen worktop and being mystified as to where they were going to and coming from I actually saw a black slug when I peered down through the grating in the sink drain.
The drain pipe went through the outside wall and down towards a drain similar to that found at the bottom of a rone down pipe. I filled the sink with hot water and Jeyes fluid to flush out any nasties, then covered the end of the sink drain down pipe with fine mesh chicken wire and that seemed to resolve the issue.
Perhaps it was just coincidence, I'll never know
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