Bubble counters

[Gowalkitoff]

I am new to co2 systems so please excuse me.  Why does the water in my bubble counter always decrease?  About once or twice a month i need to put more water back in.  Is it just kind of evaporating with the bubbles up the air tube?  There doesnt seem to be any leaking anywhere

[OttawaFolkFestivum]

Late reply: Yes, it evaporates. I've used Mineral oil to avoid this.

Here is a thread: https://barrreport.com/threads/bubble-counter-oil.8692/