I have a 30Q (7.5G) turkey fryer (burner/aluminum pot combo) that im gonna be using for my boil kettle. I make 5 gallon batches so i will be boiling 6 gallons or less. How many 60 minute boils (more or less) should i get out of one standard 15lb. tank of propane? Not sure of the BTU's of the burner. I will see if i can find out and re-post it.