Chain that won't stretch

[cpaiin]

So I've put on ~150 more miles on it.  I want to adjust the chain just a bit.  Overall, there doesn't seem to be much if any stretching. 

Now my question is, how often and with what product should I lube my chain?  Right now, I still have half a can of DuPont Teflon Chain Saver.  Is there any kind of lube that would be incompatible with the lube that came already on the chain?