If Stephen is referring to the same problem I have experienced what he is referring to is the fact that the hard water deposits build up on the emitters and the water flow slows or stops completely. That has made me pretty much give up on using drip. One of the drip supply companies sells a set of magnets that attached to the water supply line and supposedly will even reverse the build-up. I have not tried it but if anyone else has I'd really appreciate hearing about your results.
