I haven't yet found any tank to be completely leak free. I have a Davide BDC, Evod tanks, CE4 tanks, iclear16, iclear30s. I find the trick is simple, but no one seems to have mentioned this.
When storing your tanks keep them in a way that the liquid is away from the coil. For example, the iclear16 is a dual top coil tank. Simply keep it upright, as soon as you put it upside down or on it's side, the wick will eventually flood the coil and leak through the tip. For the evod tanks which are dual coil, I store them upside down (standing on the mouth tip). In the case of the Evod tanks being upside down, the coil is on top and the liquid is away from it, preventing flooding. It's a bit of a balancing act without proper stands etc, but a pen holder helps. Also when I put them in my carrying case, I put the tanks accordingly and keep the case upright.
Following this simple rule, I almost have no leaks or flooding anymore.
When storing your tanks keep them in a way that the liquid is away from the coil. For example, the iclear16 is a dual top coil tank. Simply keep it upright, as soon as you put it upside down or on it's side, the wick will eventually flood the coil and leak through the tip. For the evod tanks which are dual coil, I store them upside down (standing on the mouth tip). In the case of the Evod tanks being upside down, the coil is on top and the liquid is away from it, preventing flooding. It's a bit of a balancing act without proper stands etc, but a pen holder helps. Also when I put them in my carrying case, I put the tanks accordingly and keep the case upright.
Following this simple rule, I almost have no leaks or flooding anymore.