This is one of those topics that probably everyone disagrees with me no matter what I say.

My cleaning practice has gone between “almost never doing it” to “always doing a full clean” and many different points between them over the years.

At the moment my way of doing it is to do a very quick cleaning of my pens when I refill them, at least the ones where I don’t use a cartridge. But do a full on flush until the water is clear cleaning either when I change inks or every 3-4 refill; then I often do a full clean on everything.

While I usually have different inks in different pens, I often end up changing things around on most of them when things change.

My quick clean for piston or vacuum fillers is to just draw in some water and push it out again, while with converter / cartridge pens I first flush some water through them with a bulb syringe and swirl the nib in some water.