pH problems again

Dripping Kalk with raise your pH and get rid of excess CO2 but your problem with pH really comes from air quality in your home. If you house is shut up then there is no new oxygen getting in the home and thus no oxygen during your gas exchange at the water surface. Unless you are getting down in the 7's on pH then you should be fine. Also you need to be checking with a calibrated probe and not test strips.