
What is this and why does it keep happening?
I've had my water tested by the city, it all came back fine. Is it something in the air? Is there some type of test I can do? I am renting this apartment.
This happens in all three of my toilets, upstairs or downstairs, after sitting stagnant for a week or so. This happens regardless of how much use the toilet sees and happens even when it's been freshly cleaned.
I also had a similar weird thing happen with a watering can, and I've noticed films growing in glasses of water I leave sitting out for too long too. Watering can is the most extreme case, otherwise I only usually notice this in the toilets. Occasionally the cat's water bowl but I'm usually changing that often enough to avoid it.