Are Open Filled Cartridges Easy to Leaking?

As vaping technology continues to evolve, users are faced with more options than ever—from pre-filled pods to refillable tanks. One particular area of interest is open filled cartridges, also known as refillable or manually filled cartridges. While these devices offer flexibility, customization, and cost-efficiency, many vapers—especially beginners—often ask the same question: “Are open filled cartridges easy to leak?”

The short answer is: yes, they can leak more easily than sealed or pre-filled cartridges, especially if not handled properly. But with the right techniques, knowledge, and care, leaks can be minimized or even prevented altogether. In this blog, we’ll explore why leaks happen, what causes them, and how to prevent them to make your open cartridge vaping experience smooth and enjoyable.

1. What Are Open Filled Cartridges?

Before diving into leakage issues, it’s essential to understand what open filled cartridges are. These cartridges allow users to fill their own e-liquid or oil manually, unlike closed pods or pre-filled cartridges which come sealed from the manufacturer.

Open filled cartridges are common in:

• Refillable pod systems

• 510-thread vape cartridges

• Tanks and rebuildable atomizers

They’re popular because they:

• Offer more flavor and nicotine strength options

• Are cost-effective

• Allow reuse and customization

But this flexibility comes with a trade-off: higher risk of leaking if not used correctly.

2. Why Do Open Filled Cartridges Leak?

Open cartridges can leak for a variety of reasons. Understanding these causes can help you prevent issues before they start.

•  Overfilling the Cartridge

One of the most common mistakes is adding too much e-liquid. Open cartridges have a maximum fill line for a reason. Exceeding it can cause pressure to build up and force liquid out through the airflow holes or mouthpiece.

•  Improper Sealing

Many open cartridges require the user to close them manually after filling. If the cap or rubber gasket is not sealed tightly, liquid can escape easily. Even a small misalignment can lead to gradual leakage.

• Thin E-Liquids or Oils

Some vape cartridges are designed for thicker, higher-VG liquids or concentrated oils. Using thin, runny liquids (especially high-PG e-liquids or diluted oils) can result in leakage through the wick holes or bottom airflow.

•  Heat and Pressure Changes

Vape devices are sensitive to environmental factors. Leaving your vape in a hot car or in direct sunlight can cause the liquid to expand and leak out. Sudden altitude changes, like flying or mountain driving, can also create pressure differences that force liquid out.

• Coil or Wick Saturation Issues

If the coil isn’t properly saturated before vaping, it can lead to dry hits, followed by flooding once the liquid eventually soaks in. That excess liquid can leak into the chamber or mouthpiece.

•  Damage or Wear and Tear

Over time, rubber seals and O-rings inside refillable cartridges can degrade. If these seals become loose, cracked, or misaligned, leaks are inevitable.

3. How to Prevent Leakage in Open Filled Cartridges

Now that we know why leaking happens, here are several effective ways to prevent it.

Don’t Overfill

Always fill to the indicated maximum line—never to the brim. Leaving a bit of headspace allows for expansion and helps prevent pressure build-up.

Seal Tightly

After filling, ensure that all parts—especially caps and silicone plugs—are securely sealed. Double-check that threads are aligned correctly, and avoid cross-threading when screwing components together.

Use the Right Viscosity

Match your e-liquid or oil with the cartridge type:

• Use thicker oils or high-VG e-liquids for ceramic or large-coil cartridges.

• Use thinner e-liquids for smaller coils and pods, but avoid those that are too watery.

Tip: Look for e-liquids in the 70/30 VG/PG range for open cartridge vaping.

Let the Cartridge Sit Upright

After filling, let your cartridge sit upright for 5–10 minutes. This allows the wick to saturate properly and stabilizes the internal pressure before you vape.

Store Properly

Always store your device upright, especially during travel. Lay-flat storage can cause liquid to seep through airflow channels.

Also avoid exposing your vape to extreme heat or cold. Room temperature is ideal.

Clean Regularly

Sometimes a leak isn’t a full-blown disaster but a small seepage that accumulates over time. Regularly clean the connection points, mouthpiece, and battery terminals with a dry cloth or cotton swab.

Avoid Chain Vaping

Taking too many puffs in quick succession can flood the coil, overwhelming the wick and leading to leakage. Give your vape time to cool between sessions.

4. Are Some Open Cartridges Less Leak-Prone Than Others?

Yes. Not all open cartridges are created equal. Some brands and models are designed specifically to resist leaking through better engineering and materials.

Features to Look For:

• Anti-leak airflow systems

• Ceramic coils, which absorb thicker liquids better

• Quality seals and gaskets

• Top-fill designs, which reduce bottom leakage

Recommended Cartridge Types:

• Refillable pod systems with leak-resistant designs (e.g., Uwell Caliburn, Vaporesso XROS)

• Premium 510-thread cartridges with ceramic cores

• Tanks with adjustable airflow and liquid control

Spending a little more upfront on a well-reviewed open cartridge often saves you the cost and frustration of wasted liquid later.

5. What to Do If Your Cartridge Leaks

If your open cartridge does leak, don’t panic. Here’s what to do:

Step 1: Remove the Cartridge

Unscrew or remove the cartridge from the battery to prevent further mess or damage.

Step 2: Clean the Components

Wipe down:

• The cartridge itself

• The battery connection

• The mouthpiece
  Use a cotton swab or microfiber cloth to avoid pushing liquid further into the device.

Step 3: Inspect for Damage

Check for:

• Cracked seals

• Loose gaskets

• Warped plastic
  If any parts look damaged, consider replacing the cartridge entirely.

Step 4: Refill Correctly

If you’re refilling, be extra cautious to avoid overfilling or cross-threading. Use a needle-tip bottle or syringe for better control.

Step 5: Monitor and Test

Reassemble the cartridge and give it a test puff. If it continues to leak, it might be time to switch to a different model or brand.

6. Convenience Comes with Responsibility

Open filled cartridges provide vapers with greater control over their vaping experience, but that freedom also introduces risks—leakage being the most common. Fortunately, with proper filling, sealing, and storage practices, leaks can be minimized or avoided entirely.

If you’re a vaper who values customization, saving money, and trying different e-liquids, open cartridges are a fantastic option—as long as you’re willing to follow best practices. Remember, a little care goes a long way toward a leak-free, smooth vaping session.