Now that I have one, I was wondering how often you who use fountain pens clean them? I was just watching a Goulet Pens video, and he said every two to four weeks if you use the pen regularly, using the same ink. That got me to thinking, once I put the cartridge in, I might not want to fill it full so as not to waste ink, but then again, I don't yet know who quickly a FP goes through ink.