Fuel filter location and air in the fuel.

[tbracker]

I just read that one shouldn't locate a paper element filter on the suction side of a fuel pump as it could ingest paper particles and clog the pump. This just doesn't make sense to me.
I installed a 10 micron filter before my pump to protect it as well as the carb. A filter that creates contamination is an oxymoron.
Recently I've been having a problem with a leak somewhere in the fuel system. The engine will stall on acceleration after sitting at idle for a minute. I looked at the small glass filter I have just before the carb. and it was half full of air and the pressure was down around 3.5 psi. I tightened all the connections on the vacuum side of the pump. Pressure went back to 7.5 but after driving I had the same problem.
Could a filter on the suction side create vapor lock or am I just missing a small leak? I've put 6000 miles on this car before this problem emerged. Time to change the filter element? Could it be heat related?