Good fountain pens deserve good ink.

I once learned this lesson the hard way, when I filled my favorite pen with a bottle of ink at hand. Thinking that "ink is ink," I didn't check the brand or even condition of the ink; minutes later, my nib clogged and began to skip. I had to clean the pen thoroughly and then consider the inks I had access to before refilling with what is now a favorite. My pen wrote smoothly and without skips or blots.

The experience taught me a lot. The right ink keeps nibs gliding across the page, preserving vibrant colors — so we thought we would share this guide featuring everything you need to know about inks, including chemistry and color types, shelf life, and care tips (including what to avoid).

Fountain Pen Ink Basics

Fountain pen ink is a water-based liquid made of dyes or pigments, solvents, and flow-enhancing additives. Because it must pass smoothly through a pen’s feed and nib, it is less viscous than other writing inks and free of binders like shellac. This makes it easy to clean, but also more sensitive to evaporation, contamination, and improper storage.

Types of Fountain Pen Inks

Dye-Based Inks (Chemical Colors)

Most modern inks are dye-based, meaning the color molecules dissolve fully in water.

Well-known dye-based ink brands include Pilot Iroshizuku, Graf von Faber-Castell, Montblanc, and more.

Advantages

• Huge range of hues, including vivid purples, turquoises, and fluorescents

• Smooth flow and quick drying

• Consistent formulation with humidifying agents, preservatives, and surfactants to maintain performance

Considerations

• May fade faster in direct sunlight

• Can stain clear (demonstrator) pens if left for weeks

Natural and Iron Gall Inks

Natural inks use pigments or tannins derived from plants, minerals, or traditional recipes like iron gall (made from oak galls and iron salts).

Notable brands:  J.Herbin; (historic formulas) ; De Atramentis ; Scribo
Advantages

• Subtle, earthy tones that often darken with age

• A vintage writing aesthetic

Considerations

• Slightly more acidic; require regular flushing

• Should not be left in a pen for long periods

• Quality and consistency can vary

Specialty Inks: Shimmer, Sheen, and Scented

These inks contain metallic particles, high-saturation dyes, or aromatic compounds to create sparkle, dramatic color shifts, or fragrance. 

Brands producing shimmer inks: Pelikan (Edelstein ink); Ferris Wheel Press;  Colorverse.

Advantages

• Eye-catching for calligraphy, cards, or special projects

Considerations

• Particles can settle and clog feeds — shake gently and clean pens frequently

• Avoid leaving these inks in a pen for extended periods

• Best used in pens that are easy to disassemble and clean, not in your most valuable pen

Inks to Avoid in Fountain Pens

Not every beautiful ink is fountain-pen safe. Skip these to prevent clogs and corrosion:

• India or drawing ink – contains shellac or heavy pigments that dry rock-hard inside feeds. Most calligraphy inks fall into this category, as they contain pigments and a binder.

• Waterproof acrylic inks – form films that are nearly impossible to remove.

• Permanent markers or stamp pads – include solvents that damage plastic and seals.

If a bottle isn’t specifically labeled “fountain pen safe,” don’t risk it.

Shelf Life and Storage

Even the best ink eventually spoils. Typical shelf life is 2–5 years if bottles stay tightly sealed and away from sunlight.
Warning signs of expired ink

• Unpleasant or moldy smell

• Visible sludge or stringy particles

• Unusual color separation or watery consistency

Storage tips

• Keep bottles upright in a cool, dark drawer

• Wipe the rim clean to ensure an airtight seal

Choosing Colors and Finishes

Ink is more than black or blue. Today’s market offers classic business blues, subtle grays, and vibrant seasonal editions.

• For professional documents, look for archival or “bulletproof” black and blue.

• For journals and art, try shading inks that create natural gradients or shimmering metallics for accent work.

• If you mix inks to create custom shades, stay within the same brand and formula to avoid chemical reactions.

Maintenance and Best Practices

• Flush pens every few weeks or when changing colors.

• Use a bulb syringe or converter to wash with cool water until it runs clear.

• Never let ink dry out in a pen—dried dyes can take hours to dissolve.

• Rotate pens so no single pen sits inked for months.

• Test new or unknown inks in an inexpensive pen first to ensure compatibility.

Conclusion

The perfect fountain pen ink combines color, chemistry, and care. Whether you lean toward natural earth tones or dazzling shimmer, the key is to choose inks labeled safe for fountain pens, store them properly, and clean pens regularly. A thoughtful approach keeps your writing instruments performing beautifully and your words looking their best for years to come.

And that ink-at-hand I tried? We no longer feature that brand at The Pleasure of Writing.