Hi Magnus,
Thank you for your reply! The water in the tray is not rain water, it is filtered water... I was hoping to be good enough. In any case I will buy distilled water and used that from now on.
What do you think about filtered water? I just have a regular water filter which claims to remove this from water:
Lead up to approx. 99,5%
Copper up to approx. 98%
Cadmium up to about 99%
Phenol not more than about 99,5%
Benzene up to about 99%
Pesticides up to approx. 95%
Chloroform up to about 99,5%
Chlorine up to 100%
Thank You,