THOUGHT I'D SHARE WHAT I BELIEVE CAN BE A QUICK SAVE.
After having a few of my mods fail, to what I believe was juice leaking down the 510 screw port, I started using these.
A hole puncher makes a very close fit to the 510 threaded bottom of all tanks.
Placing 1 or 2 of these paper washers on the tank bottom has stopped the leak from getting into the mod.
Also lets you see how much the tank is leaking..