Agreed. My duty is to ensure that gas and electricity have the required safety certificates (they do) and that incoming water and waste water pipework is in a satisfactory condition. they are.

What the my tenants put down the drain, I can only ask then not to, but obviously, I have no control over that. They tell me they do wipe off any cooking oil before washing; there is no dish washer, only a clothes washing machine.

I really have no idea why this has become an issue when to the best of my knowledge, including when we lived there, it was not.

Have sent the mp4 to the g/f but no immediate response.