How does the atomiser’s liquid supply work?

The atomiser’s liquid supply relies on capillary action and gravity. The liquid flows around the coil body, enters through the juice holes and is drawn into the coil by the cotton. When you take a puff, a slight vacuum is created, which draws in additional liquid. Factors affecting e-liquid flow Viscosity: 50/50 e-liquids (PG/VG) flow quickly and are suitable for MTL coils with 0.8–1.2 ohms. 70/30 short fills are thicker and require larger coil openings, typically found in sub-ohm coils below 0.5 ohms. Cotton loading: Too much cotton blocks the juice holes; too little allows e-liquid to leak and causes gurgling. Power: The higher the wattage, the faster the liquid evaporates – the refill rate must keep up. Filling level: Nearly empty tanks deliver less pressure; with some vapes, this results in weaker puffs.

Verdampfer & Coils

Liquid flow on the vaporizer - understand and optimise

Correctly adjust the liquid flow on the vaporiser: Tips against dry puffs, gurgling and too much liquid. Including tips on coils, winding and suitable tanks.

The e-liquid flow determines whether your vape produces a smooth vapour, gurgles, or delivers dry hits. This refers to the amount of e-liquid that reaches the coil from the tank per unit of time and is vaporised there. Too little e-liquid burns the cotton (dry hit), too much floods the coil and causes e-liquid to leak into the mouthpiece. In the following guide, you’ll learn how e-liquid flow works technically, what factors influence it, and how to adjust it to suit your coil, e-liquid and draw – whether you’re using an MTL pod system or a sub-ohm tank.

E-liquid flow describes the transport of e-liquid from the tank through the wick holes into the cotton and finally to the heating coil. The cotton absorbs the e-liquid via capillary action, and the coil vaporises it with every puff. To maintain this balance, approximately as much e-liquid must flow in per second as is vaporised.

It is important to distinguish this from airflow: airflow regulates the air flow, whilst liquid flow regulates the e-liquid supply. However, the two are linked – a wide-open airflow at high power (e.g. 60–80 watts) vaporises more liquid and therefore requires larger coil openings or a thinner e-liquid. With pre-built coils, the manufacturer sets the juice holes; with rebuildables, you determine the setup.

The atomiser’s liquid supply relies on capillary action and gravity. The liquid flows around the coil body, enters through the juice holes and is drawn into the coil by the cotton. When you take a puff, a slight vacuum is created, which draws in additional liquid.

Factors affecting e-liquid flow

Viscosity: 50/50 e-liquids (PG/VG) flow quickly and are suitable for MTL coils with 0.8–1.2 ohms. 70/30 short fills are thicker and require larger coil openings, typically found in sub-ohm coils below 0.5 ohms.
Cotton loading: Too much cotton blocks the juice holes; too little allows e-liquid to leak and causes gurgling.
Power: The higher the wattage, the faster the liquid evaporates – the refill rate must keep up.
Filling level: Nearly empty tanks deliver less pressure; with some vapes, this results in weaker puffs.

In practice, adjusting the e-liquid flow means finding the right balance between coil, e-liquid and power. These points will help you:

Choose a coil to suit the e-liquid: If you’re using a 70/30 VG e-liquid, opt for sub-ohm coils with larger juice holes (e.g. 0.15–0.3 ohms). For nicotine salts and 50/50 e-liquids, tighter MTL coils from 0.8 ohms upwards are recommended.
Stick to the recommended wattage range: Every coil has a range, usually printed on the side. If you go below this, more e-liquid will flow in than is vaporised – the result is too much e-liquid in the chimney and gurgling.
Prime the new coil: Pre-soak the cotton with 4–6 drops of e-liquid and let the filled tank rest for 5–10 minutes before taking your first puff.
Adjust the airflow: Too little airflow creates strong negative pressure and can suck e-liquid through the coil. Open the airflow gradually until the draw is smooth.
Store the tank upright: Vapes stored lying down allow e-liquid to run into the chimney. This causes spitting on the first draw.

If you want to let the e-liquid flow through without flooding the coil, it helps to pause briefly between puffs – usually 5–10 seconds is enough for the cotton to become fully saturated again.

Why is my vape suddenly gurgling?

Gurgling is usually caused by too much e-liquid in the chamber. Common causes include too low a wattage setting, an unprimed coil, or a tank that has been transported lying on its side. Empty the chamber, blow gently through the mouthpiece and increase the wattage to the manufacturer’s recommended range.

What should I do if I get dry hits despite a full tank?

A dry hit means that the cotton is being vaporised dry. Either the e-liquid flow is insufficient (e-liquid too thick, juice holes too small) or you are taking too many puffs in quick succession at high wattage. Reduce the wattage or switch to a coil suitable for 70/30 e-liquid.

How often should I change the coil?

Depending on usage, a coil lasts 5–14 days. If the flavour becomes flat or slightly burnt, the flow is being obstructed by residue. Sweet e-liquids with a high sweetener content significantly shorten the coil’s lifespan.

Is it okay for e-liquid to get into my mouth?

Small amounts are harmless but unpleasant. If e-liquid regularly leaks through the mouthpiece, the e-liquid flow is incorrect – check the coil, seals and the fill level. The product is also intended for adults aged 18 and over only.

A properly adjusted e-liquid flow is the basis for consistent flavour and even vapour production. Pay attention to the interplay between coil resistance, e-liquid mix ratio and wattage – this will help you avoid both dry hits and too much e-liquid in the chamber. In our selection of vaporisers, you’ll find models for MTL and sub-ohm vaping, along with suitable coils and compatible e-liquids to compare and test.