After 3 days fermenting I started reducing the temperature.
Suddenly the humidity dropped from 95% to 65%. I tried to rectify this by putting some salt water trays in the fridge. First one tray and then another to make about 4 sq ft of surface area!
The humidity continued to drop to 60% which is where it has been for the last 4 days. WTF!!
NOW the penny has dropped! I was using overly saturated salt water so the extra salt was taking humidity out of the air!
I now have a couple of trays of lightly salted water in there and the humidity is about 70%. I might hang a towel in there as well but as I've just made the change I will wait a few hours.
Hope they are not irretrievably case hardened!
'ope they've fermented
'ope they're not poisoned by fungus
and so on and so on
At the start of the 8th day they are at 13-15C and hopefully over 70%. They have lost 23% weight in a week. 45mm diameter casings.