Not again :(

[Pajarita]

Do you have a hygrometer in the room where they are kept? Do you use a humidifier when the humidity is too low for them? Do you have central A/C? Is it possible that there is something in the ducts? Do you use bottled water for them?

[marie83]

No monitor but we do keep it more humid than we would like. We don't have A/C or even the heating on apart from really cold days. They get filtered water these days but the used to have tap, then bottled until we got the filter.