One of the most common reasons for leaky tanks is also the most simple. If the tank isn’t fastened together properly, either through cross-threading or simply not being screwed together tight enough, e-juice can leak out of the openings. First check to see that the threads are in sync and fastened correctly, then fasten tightly to ensure the tank is airtight. Be careful not to screw it together too tightly, since this can cause issues in itself. Find your tank’s sweet spot and stick to it. If the threads are crossed, unscrew and screw it back again. If the same happens, you might have to replace the tank entirely. Similarly, if the threads are worn away from overuse, it’s very difficult to fix and you’ll most likely have to buy a replacement tank. Thankfully, most high-quality modern tanks are made of sturdy stuff and often employ top-fill systems which reduce strain on the threads.