Product Tips


ZenZoi® Fountain Pens are crafted to accept either a disposable ink cartridge or an ink converter (usually included inside the pen's barrel)

Using your pen

  • Fountain pens are design to be held at 45% angle.
  • Don’t press too hard, relax your grip when using your pen
  • Protec the pen’s nip by keeping the cap on when no using it
  • Ink dries, so wash the pen with water regularly or when necessary
  • Don’t write on rough surfaces

Ink Cartridge Installation

ZenZoi® Fountain Pens use an international standard size cartridge. Premium ZenZoi® Fountain Pens have Schmidt Nibs and they need special international standard size cartridge. (See Below)

  1. Remove the pen’s cap
  2. Unscrew the pen’s barrel (grip section)
  3. Remove the empty converter (If still inside)
  4. Insert the ink cartridges in the nip section of the pen (see below)
  5. Screw the pen’s barrel (grip section)
  6. Allow the ink to flow to the nip tip.

Please remember to wait few minutes and shake your new pen downwards few times dynamically after inserting the very first ink cartridge to jump start the ink flow.

It's done correctly you should see first drops of ink come out through the pen's nib (which will get the nib initially a bit moist). For Premium pens there is no need of shaking the pen. Best if you do this process above a piece of paper or above the kitchen sink to not stain your surroundings.

Ink Converter Installation and Refill

The use of the converter require a more detail explanation (see video below about ink converter refill) (There is one empty inside ZenZoi™ fountain pens)

Ink Cartridges vs Converts

    Fountain pen users have the convenience of choosing between two filling options. Cartridges are easier and less prone to creating a mess while converters are more cost effective and provide a sense of nostalgia for old-fashioned pen users.

    • Converters, if cleaned often after filling of the ink, can be reused for many years and do not need to be replaced often. 
    • Disposable ink cartridges have to be replaced more often (less ink fits the cartridge than the converter) and are less cost effective than a bottle of good ink. (ZenZoi® fountain pens use international standard size 1.5” or 3.8 cm). 

    Pros: Fountain pen users have the luxury and convenience of choosing between two filling options. Cartridges are easier and less prone to creating a mess while converters are more cost effective and provide a sense of nostalgia for old-fashioned pen users.

    Cons: Disposable ink cartridges have to be replaced more often and are less cost effective than a bottle of good ink. Filling using a converter can be messy for the novice fountain pen user and may require more cleaning or maintenance.


    Best rollerball pens are an excellent choice for everyday writing tools, superior to ballpoint pens and even fountain pens. They are easy to write with and their ink dries quickly, which is why they are also great for left-handed people. 

    Rollerball pens use the same mechanism as ballpoint pens but have water-based ink, making the writing process smooth and satisfying.  The main benefit of a rollerball pen is the flow of ink, which won’t stop when you are in the middle of writing, as often happens with ballpoint pens. Overall, the writing experience is similar to writing with a fountain pen, with the advantage that the rollerball pen doesn’t smudge. Your fingers and clothes will stay clean, and your hand won’t feel any tension, as the writing process is intuitive and easy.

    While rollerball pens do need to be refilled more often than other types of pens, the result is worth it.

    The best rollerball pen will be a great surprise gift for anyone, because it’s always handy and easy to carry with you. It will appeal to those who enjoy writing, drawing, or just carrying around nice things. Spoil your loved ones, co-workers, or business partners with a nice gift that they will surely appreciate.

    Most of our rollerball pens come with ink refill cartridges already so you can enjoy your pen as you open the box. 

    Rollerball Pen Ink Refill Installation

    • Unscrew the barrel
    • Pull refill out
    • Insert a new refill
    • Screw the barrel back

    Rollerball Pen Ink Refills

    ZenZoi® pens use standard rollerball ink refills. 

    Size: 4.3 inches (110 mm) long x .2 inches (6mm) diameter.

    Recommendation: Schneider Topball 850 0.5mm or Schmidt Safety Ceramic Roller 888

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    If you are looking for professional ink to refill your favorite fountain pen, you are in the right place. We have created long-lasting, eco-friendly fountain pen cartridges to provide you with a fantastic handwriting experience. 

    Are you tired of reordering your ink cartridges so often? We offer big fountain pen cartridge packs to ensure that you won’t run out of ink to quickly. Our cartridges are perfect for both professional and everyday artistic use, with affordable prices and convenient online shopping options.

    The main benefits of any fountain pen cartridge by Zenzoi are:

    • Non-toxic composition – our ink contains no harsh chemicals and has a neutral PH scale, making it safe to use;
    • High-quality ink – our special smooth formula guarantees great flow with each stroke;
    • International size – all cartridges come in a standard size so they will fit almost any fountain pen you choose;
    • Planet-friendly manufacturing – we avoid harmful plastic and use only eco-friendly materials caring about the Earth;
    • Great selection – our online shop offers a variety of choices: From classic black colors to bright colored summer collections;
    • Big packages – there is no need to buy several small sets, just purchase one 24-cartridge pack and enjoy great ink for a long time.

    Common types of fountain pen cartridges

    International Size Ink Cartridge Refill

    cartridge for pen

     Although International Standard Size Cartridges have the same size (1.5" or 3.81cm), the suction part of the cartridge can vary on length. ZenZoi® Premium Fountain Pens use 2.3mm long suctions feed, made for German nibs.  This type of cartridges can be use in all other ZenZoi® Fountain Pens

    You should be able to easily recognize these proprietary cartridges as their shape or size does not meet international standard, is odd and fits just one brand selling them. Some examples are below. 

    Examples of non-standard ink cartridges that would fit only

    The Brand That Makes Them

    fountain pen cartridge
    fountain pen ink cartridge

    Final Tip

    When buying ink cartridges for your ZenZoi® pen please get cartridges shown above and stay away from branded ones as they often fit only one particular brand that sells them (typical practice of some brands to lock users with their brand).

    If you are inserting the very first cartridge into your pen, shake it downwards to start the ink flow. Remember that ink drops make nasty stains, so do this above the safe surface (a kitchen sink or a sheet of paper).

    Ink Converter Refill Process

    Another option for refilling your pen is bottled ink. You would use the converter included inside your pen to draw ink directly from any ink bottle of your choice.

    The most commonly used types of inside converters are piston and squeeze types. 

    The one we use with our pens is piston type (as we find it more precise and not causing air bubbles) which is included inside the barrel of every Zenzoi® fountain pen. 

    This youtube link below shows how to refill piston type of converters by placing the nib inside the ink bottle and twisting the converter:

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