Storing ink so it lasts, and the small habit that saves the whole collection

Ink keeps for years if stored sensibly and goes off surprisingly fast if not. What actually matters.

Storage

• Cool, dark, upright, closed. Light and heat are what degrade dyes, and a bottle on a sunny desk is the most common way a colour shifts.
• Upright so the seal is not sitting in ink, which is what makes caps stick and eventually leak.
• Do not decant into anything that is not glass or a known-safe plastic. Some inks react with cheap plastics over time.
• Boxes are ideal. A drawer is fine. A shelf in daylight is the problem.

The habit that matters most: never fill from the main bottle after the first few times
Every fill introduces whatever is on the nib and a little air. Decanting into a small vial and filling from that keeps the main bottle sealed and uncontaminated. It also means a contaminated vial costs you a few millilitres rather than a whole bottle.

Date everything. A small label with the date opened. Ink does not have a hard expiry, but knowing a bottle has been open for six years explains a lot when it starts behaving oddly.

How to tell an ink has gone

• A smell that is sour or mouldy rather than neutral.
• Visible strands, floating specks or a film on the surface.
• Sudden flow problems in a pen that is otherwise clean.

Mould is the real risk and it is usually introduced from a pen or a finger rather than being spontaneous. If a bottle has it, discard it rather than filtering, and check anything stored next to it.

Organising: by colour rather than by brand, because that is how you actually choose. A written swatch of each on the paper you use is worth more than any photograph.