Sub ohm vaping, also known as direct-to-lung, is a style of vaping categorised by large cloud production and lots of flavour. Sub-ohm devices are typically much larger than MTL vapes as they require bigger batteries and more power to vapourise e-liquid at higher temperatures. These devices require coils with a resistance below 1.0 ohms. This style of vaping is named direct-to-lung vaping because of the way the vapour is inhaled directly in your lungs. This differs from the other most popular style, mouth-to-lung vaping whereby the vaper will hold the vapour in their mouth before inhaling into their lungs.

Nic salts are not made for sub-ohm vaping. Nic salts have a high nicotine strength, and unlike other forms of nicotine-based e-liquid, they have been made in a way that allows them to be absorbed rapidly into the body. The throat hit and nicotine hit would be far too much if they were to be used with a sub-ohm vape due to the amount of e-liquid that is being vapourised in comparison to lower wattage MTL devices.

The answer to this question is slightly vague as there's no specific answer to it. There are quite a few factors at play that affect how long your coils last, but being aware of them can help to extend their life. One of the most key factors in how frequently you vape. The more you use your sub-ohm device, the quicker the coil will burn out and a sub-ohm replacement coil will be needed. For the heavy vapers out there, their coils will likely need replacing in a week or less, where less frequent vapers may not need to replace their coil for up to 2 weeks. 

This next one is a very important one, but in many instances it's often overlooked or ignored. Using the right wattage settings on your mod that correspond with the resistance of your coil is very important to ensuring you don't burn it out prematurely.

Washing your coils can help to extend its life, however it is not a fix for a completely burnt out coil. If the coil is burnt out, it means it's time for a replacement coil, however cleaning it beforehand can help vapers get an extra few days out of their pre-built coils.

An ohm is the measurement used to gauge the resistance of a coil. The higher the ohm, the greater the resistance.

Using the right e-liquid is essential in order to get the large clouds of vapour and intense flavour that sub-ohm vaping is known for, but also to ensure that you do not damage your vape. E-liquids are made up of two main ingredients; Vegetable Glycerin (VG) and Propylene Glycol (PG). Depending on the ratio of these two ingredients, they will either be better for sub-ohm or plus-ohm. Sub-ohm vaping requires thicker e-liquids that are higher in VG, typically with ratios of 70/30 or 80/20. Using higher PG e-liquids in your sub-ohm vape tank can result in damaging it, leaking or burning the coil.