I just got the kit in and I pulled the tank out of the box and went to take the cap off and I couldn't. There are two little arrows pointing at two dents in the side of the cap. How do I get it off.
1. Go to gym & lift some weights
2. Push down hard & give it a firm twist to the left
3. If #2 doesn't work, repeat #1 as necessary
Seriously, try tapping the cap with a rubber mallet. Also, push down VERY hard while simulataneously twisting to the left. While twisting keep downward pressure and it should come loose.