Yes! Also Rohrer and Klingner is another I like that's cheaper from them, R&K's SketchInk is waterproof and nice with watercolors (I like the muted red Jule)

Rohrer & Klingner sketchINK 50ml

Rohrer & Klingner have been making ink since 1892, and by hand, too, using well-established recipes. Their sketchINK ® is ideal for artwork as well as normal fountain pen use. It's also waterproof...

CultPens also runs a buy four inks get one free sale every once in a while also, it looks like it's currently going on- I like it as an opportunity to try something new if I'm already planning on buying things (I tend to keep a list and order from there once a year or so when I have enough to get)