as for spotting air leaks....
they are probably my #1 most frustrating problem in nitro. If i suspect an air leak, as i suspect you may, I first wrap zip ties (tiny ones) around all of fuel line connectors (at the barb) and rub a little permatex around the fitting the fuel line connects to. if I still have the problem, i replace the fuel lines, then the fuel tank. replacing the whole shebang will cost maybe $20 for everything, and its worth saving yourself the headache. just smart small. zip tie the fuel line barbs, permatex the tank, and if all else fails replace the fuel lines, and then the tank.