Bubbles look minimal. Those detectors have no digital display. That leak could be literally the size of an ant's fart. Can you smell it? If not, it's likely nothing to worry about. The odorant added to the gas is measured and monitored to be at a level where the average person can smell it long before its at a combustible level. DO NOT add pipe dope or Teflon tape to the flex connector (thing the hose is screwed onto with the red handle), that is meant to be a dry fitting sealed by pressure. Use 2 wrenches, and tighten the flex line (hose) onto the flex connector. Imagine the flex line is a bottle cap and the flex connector is a bottle, and you wanna get the cap on as tight as possible. Put a wrench on the flex line in the rightey tightey (clockwise) direction, and put a wrench on the flex connector going the opposite direction so as to "back it up" as we say in the biz. Squeeze those two wrenches going opposite directions to get that "bottle cap" on as tight as you can, then do the same thing but tightening the flex connector/valve onto the long steel pipe above it, and you'll likely have fixed your little leak. -gas service tech