Sorry for bringing up an old topic, DrCodfish, is your peli BT fine with the Ancient copper ink? any staining or adverse effects?
I haven't had any trouble, but I don't let that or any red hued lay around in any of my pens. I go along with what Rick Propas said, not because he said it but because I made mistakes with red inks before I knew better. If you stick with half fills in your pens you will come to a point where you have to make a conscious decision about putting more red ink (or any color really) in your pen. An easy way to avoid a mistake due to forgetfulness.
As Will Rogers once said "Good judgement comes from experience, ... and a lot of that comes from bad judgement".