On the Magma grill you unscrew the the grill regulator leaving the "venturi tube" open. It has a notch in it. You screw one end of the control valve ( step down pressure regulator and also controls th flame), permanently into on end of the hose assembly to the tank. The other fitting on the control valve fits into the Venturi Valve opening and clicks locked with the notch.
We too have to leave the propane hatch open when grilling. The hose is neatly coiled hanging on a line holder in the compartment. We never had to worry about running out of fuel in mid meal and it was a real convience not carrying the bombs.
MAGMA Control Valves for Magma Grills at West Marine
The new Magma grills ( ours in 2 years old) is a real improvement from the older kind in terms of staying lit and we no longer have to worry about the damn lid clanging of the side of the boat.
For added culinary experience we have a small contasiner of applle wood chips on board. I usually soak a few in H20 about 10 minutes before lighting the grill and then throw them on the ceramaic brickets. Imparts a great flavor to fish/ meats and veggies.
I cant tell you how many of my friends have these grills and love them as we do and how many of them done have the brickets in them. They help control the flames, and direct heat, they almost interlock when placing them in, and the prevent the orafices of the burner assembly from getting clogged and dirty as quickly.
last October on our last anchorage of the season we made smores on the grill with the people we rafted with and HOt apple cider with Applejack. Was a memorable eving.