Ink and watercolor are my favorite combo of paint supplies. They complement each other so well and also seem to add an element of surprise and unpredictability. The main inks that I use are from PH Martin's Bombay Ink line. I'm always on the lookout for other inks – but these are the sets I've used most. I use these with brushes and with calligraphy pens depending what I'm trying to accomplish.
And lastly – my favorite white ink is Copic Opaque white ink. If you are curious as to how I use this – make sure to check out the blog post below.