How to fill an electronic cigarette: explanations and advice

An electronic cigarette works on the principle of a heating resistor which vaporizes the product. It consists of 3 essential elements for its operation.

The clearomizer is the part of the electronic cigarette that contains the liquid, in addition to being the liquid reservoir, it allows by its design to offer a tight (MTL) or aerial (DL) draw. It will also affect how we fill electronic cigarettes with liquid.

The resistance or wick allows the vaporization of the product, it is composed of a conductor and a cotton membrane. By heating the conductor, the liquid vaporizes.

Finally, the battery is the element which allows the heating of the resistance. It sends a current to the conductor of the resistor to cause heating. Its design will allow you, depending on the model, to access advanced modes, and to have more or less autonomy.

Filling the electronic cigarette

There are several types of tanks that have different manipulations. We will see here the main types of tanks.

The bottom filling clearomiser:

It was the most widespread model at the beginning of the vape with the Aspire Ce5 or Kangerteck T2 tanks for example. This type of filling still exists today on models like the GS AIR or the Q16.

  • Unscrew the clearomizer from the battery.
  • Unscrew the base of the clearomizer.
  • Fill the tank with liquid (do not put it in the middle hole, but on the sides).
  • Reassemble the base.
  • Reassemble the clearomizer on the battery.
  • If your resistor is new, wait 10 minutes for the resistor to soak.

The Top Fill Clearomiser:

This is the most popular filling method on the market! This process offers many advantages, it allows you, for example, to avoid getting your fingers full of it, or risking spilling it. In addition, this method is faster and it does not require separating the clearomizer from the battery. 

  • Unscrew the upper part of your clearomiser (sometimes 1/4 turn is enough).
  • Fill the liquid (on the sides and not in the hole in the centre).
  • Screw the upper part back on.
  • If your resistor is new, wait 10 minutes for the resistor to soak.

The Clearomizer with fast filling: 

They are a derivative of those with top filling, they allow even easier and faster filling. They are beginning to represent an important part of the clearomizers currently on the market such as the Zenith from Innokin, the Melo 5 from Eleaf or the NRG-S from Vaporesso. Unlike those with top filling, there are several types of openings. In general, an inscription is present to tell you which way to turn or push to open it.

  • Push on the upper part to make it slide. 
  • Fill the e-liquid into the hole.
  • Push the other way to clip it.
  • If your resistor is new, wait 10 minutes for the resistor to soak.

Filling Pod cartridges:

In a somewhat special case, the cartridges of the pods are not clearomizers but have the same function. They represent an alternative to conventional electronic cigarettes by being lighter and more compact. The pods often have the same filling system, just the procedure for removing the cartridge changes, sometimes in addition to shooting it, you have to press a button to extract it like on the Aegis Boost pod. There are also models where it is not necessary to remove the cartridge, in this case, skip step 1.

  • Remove the cartridge from the pod.
  • Locate the filler tab.
  • Pull it to release the filler hole.
  • Fill the cartridge.
  • Replace the tab.
  • Replace the cartridge.
  • If your resistor is new, wait 10 minutes for the resistor to soak.

Why wait for resistance to imbibe?

The resistance of your device consists of a conductor which heats an absorbent material (cotton). If you do not wait for the liquid to soak into the cotton when it is new, you risk burning the cotton at the time of the first shoot. Once this cotton is burned, a burnt taste is felt and it is irrecoverable, you will be good to change the resistance. To be sure to have a well-soaked resistance, we advise you to wait 10min.

When to refill your electronic cigarette?

Filling a clearomizer is simple and despite their more or less high capacities and their consumption, sooner or later they will have to be filled. You can refill it at any time, no need to wait for the tank to empty. However, the fluid level should not be allowed to drop to a critical level. Indeed, your resistance could no longer be soaked and therefore burn. As a general rule, you have to make sure you always have 1/4 of your clearomiser filled to avoid problems.

Tips for choosing your e-liquid

The e-liquid is the product that will be vaporized by your machine, it has a direct impact on the life of your coils. On each e-liquid is indicated the rate of Propylene Glycol (PG) and Vegetable Glycerin (VG). This rate, commonly known as the PG VG rate, mainly affects the viscosity of your liquid. The higher the PG level, the more fluid your liquid will be, conversely for the VG level.

Example :

  • e-liquid in 70/30 = fluid e liquid
  • e-liquid 30/70 = thick e liquid

How to choose the PG VG rate?

This rate is to be taken into account according to your machine. Clearomizers with a tight draw are mainly compatible with fluid liquids with a minimum of 50% PG. If you put an e-liquid with a PG VG of 30/70, for example, you risk having a liquid that will soak your resistors badly and therefore wear them out more quickly.

Clearomisers with a more airy draw will need a rather greasy e-liquid. The design of their resistors makes them have large orifices for the liquid. If you put an e-liquid that is too fluid, you risk having problems with leaks.


So! We have seen that there are several types of clearomizers. They have their particularities in terms of filling. We have presented our techniques for filling each type of clearomizer and how to choose your liquid. Do not hesitate to consult our other articles on electronic cigarettes.