>>> špricer.
>>
>>Ouch. I'm a bit blind on the red sensors - this is not readable. What is wrong with black-on-white .... grumbling
>>
>>špricer sounds a bit like german "Spritzer" .
>>
>>Water from the tap does the trick. :)
>
>You have carbonated water on the tap? It's been decades since I last went to Germany...

A bit chlorine, carbon dioxide etc. At least it is more then the partial pressures at 20°C allows. It is out-gassing.
I have problems with it on the fish tanks...