It has leaked about a centimeter in two days I've checked all the connections and there are no visible losses. All the metal clamps are screwed tightly, but not too tightly.
I'm seriously thinking it's the cap. Do you guys recommend another one? I heard in the past metal ones are better?
better picture of the cap I'm using:
I got the cap and the end both at Home Depot...and the cap itself is a bit 'short'. As you can see in the picture, there is still thread left, but it won't cap more
btw,the first picture is my current setup. I changed the T-line's location and cleared up the cables