WHY IS MY TANK LEAKING?
The most important thing to know is that all thanks can leak and that leaking is caused by a few very clear reasons and it can easily be fixed and managed.
Although tanks and coils are getting pretty good these days, the reality is that all tanks will leak under certain conditions. This is because the coil is made from a porous wicking material which has the potential to become over saturated and then leak. As we vape we are drying out the wick which will cause the wicking material (cotton) to become less saturated and therefore vaping itself will stop (or slow down) the leaking.
Most commonly tanks leak through the coil and out the air hole. In rare cases they leak from the O-ring seals, which can easily be replaced with the included seal kit that comes in the box when you purchase a tank. For the vast majority of cases thanks leak through the coil and out the airflow hole. This is because the coil has become over saturated with e-liquid and is precipitating out the bottom of the coil into the base of the tank and then out the airflow hole.
Below are shown some of the main reasons that can cause tanks to leak, and what to do.
VAPING TOO LOW
The recommend wattage range is typically engraved on the side of the coil. The wattage range is specified so that the heat produced is enough to evaporate the e-liquid from the coil and dry it up enough so that fresh e-liquid from the tank will move back into the coil and re-wick the coil at the right rate. The coil resistance, size of the wicking holes and cotton (wicking material) density is specifically designed to work efficiently, and not leak through the coil, when used at the particular specified wattage range.
If you are using your coil below the recommended wattage range, the tank will eventually leak or there is a higher chance that it will leak. This is because, not enough e-liquid is evaporating away from the coil when heated and slowly more and more e-liquid is wicking the coil and eventually it becomes oversaturated causing it to drip through the coil and out the airflow.
The best thing to do in this case just turn you device up a bit and give it a few long draws in a row to dry the coil out and then it will stop leaking.
VAPING TOO HIGH
If you are using the coil above or close to the maximum recommended wattage range, the e-liquid will get hot around the coil causing it to loose viscosity (become thinner), which will increase the chance of the coil becoming oversaturated. Oversaturated coils will leak.
In this case just turn your wattage down a little and your juice wont get so hot and you will stop the leaking or at least reduce it a lot. If you like vaping at high wattages try getting a coil that have a high wattage range. Most coils come in a range of different resistances which have varying different operating ranges. Lower resistant coils have higher wattage ranges.
You can also heat the e-liquid by chain-vaping, even when operating the coil within the range. When vaping consecutively, you are not allowing the coil to cool that little bit before reheating it again and the e-liquid around the coil becomes very hot causing it to thin out. Often after a few big draws in a row you will get a little bit of juice leaking from the coil.
The best thing to thing to do in this case is slow down your vaping a little. Alternatively you may be chain-vaping because your not getting enough vapour, so upgrading to a tank with larger airflow and lower resistant coils will give you a bigger hit and my help. Also increasing your nicotine strength will mean that you wont need to take as many draws to get the same amount of nicotine.
E-liquid is made of Propylene Glycol (PG) and Vegetable Glycerine (VG). The Vegetable Glycerine (VG) is thicker than the Propylene Glycol (PG) and e-liquids that have more than 50% PG will be thinner than e-liquids that have more than 50% VG. Most tank coils are designed for a thicker e-liquid, therefore e-liquids that have more than 50% VG. The standard ration of e-liquid is 60-70% VG and 30-40% PG. Thinner e-liquids will when used in modern tanks will result in leaking. It is important to check the VG:PG ratio prior to purchasing your e-liquid. Thin e-liquids are still available and are normally used in small pen style cigalikes and other vaporizers with very small coils and very restricted airflow.
If you have a thin e-liquid there is really no way to stop your tank from leaking. One option would be to increase the wattage a little and try to dry up the coil a little more, but the heat from doing this would potentially cause even more leaking.
In the same way that the heat from your coils thins out your e-liquid when firing the coil, a hot day or hot environment will also thin your e-liquid. For example leaving the tank in a hot car or in direct sunlight will often result in the tank leaking. If this happens just let your take cool a little and vape out the excess e-liquid from the over saturated coil to dry it up and your tank will stop leaking.
If your coil is wearing out, it wont hold the e-liquid as well as a new fresh coil. Over time the wicking material (cotton fibres) in coils deteriorate and become more porous than normal. Usually after a week of continuous use a coil will start to leak a little. If the coil does not taste burnt and the leaking is minor, then continue using the coil. However a simple solution to a leaking tank with a coil that is a week to two weeks old, is to change the coil for a new one.
E-liquid pressure in the tank is also a reason why some coils become over saturated and leak. Often this is also because the coil is old and worn out. When filling the tank liquid pressure is placed on the coil and after closing the top cap sometimes additional pressure can occur in the tank. Most coils can withstand this pressure without becoming over saturated and leaking, but older coils will have a higher chance of leaking from pressure.
The easiest way to equalise the pressure in the tank is to turn it upside down and open the airflow hole fully. This will allow the little bit of compressed air in the tank to be released through the coil and out the bottom airflow hole.