First let me say I choose most inks based on how easy they are to clean out of my pens. I don’t want to spend half an hour on one pen and take the section out and scrape glitter out of the feed with a brass shim. I’m not interested in that. If you don’t mind it, use whatever ink you like. 🙂
Anything that turns to jelly like this bottle of Private Reserve (this was from an old batch – I’ve been told that they’ve fixed their recipe and PR is a safe ink to use) or inks that separate when sitting for a few hours – some inks from Diamine or Noodler’s – I avoid like the plague. JUST because they take a little longer to clean out, remember.
I avoid shimmer and glitter inks too.
Now – I’m not saying you should avoid these inks, or that there’s anything bad or wrong with them. I avoid them. I like easy to clean inks and water proof writing isn’t important to me.
Diamine Lavender separated in the converter…
I decanted the lavender into an empty bottle once the sediment settled so I could use it without the headache. Is the color a little different? Yes, but it’s still purple, and for me that’s good enough.
What are some inks that I consider safe (easy to clean)? Sheaffer, Waterman, Parker, Pilot, Pelikan, Montblanc, Monteverde, and a few colors from Diamine (ones with no sediment), R & K, DeAtramentis, KWZ, and I know there are more, but I mostly stick to Sheaffer and Waterman for tuning my nibs, so that’s where my experience lies.
But listen, my friends at Vanness could tell you better than I could about what inks you should really avoid, but most of them are fine to use if you don’t mind a little more time at the sink. There are THOUSANDS of colors to pick from, hundreds of brands. Have fun and enjoy your pens. 🙂