Ian Grant
Subscriber
I'd add another possibility which I've had here in Turkey. The water is very hard, calcium builds up in the pipes particularly the hot water to the extent that there's small filter on the end of the kitchen tap's spout that blocks every few months. The cold water only needs hot water added when mixing dev in the winter and then particles can be present in the developer and these can end up on the emulsion. They are quite difficult to dislodge & they don't wash off easily later, this caused me quite a problem just after Christmas this year.
Ian
Ian