On the subject of inks.

What ink to use is a very personal choice, and there are many different companies producing inks in every colour imaginable (even UV light reactive invisible ink!).

I mostly use inks from two companies:
Diamine - an English ink company, based in Liverpool since 1925, but making inks since 1864.
J. Herbin - a French ink maker, based in Paris since 1670.

This is because they produce inks in a range of really nice shades that are free flowing and, most importantly, reasonably pH neutral so the shouldn't corrode the insides of my pens.