I would really really like to see a picture of this split PEX. There seems to be a lot of drop a bomb on PEX and run postings. You see the plumbing industry is a bit gun shy on plastic piping. In the 1980's we went with a wrong material called Polybutylene while the rest of the world went with PEX. Who would have known chlorine eats Polybutylene? This led to a huge class action lawsuit and rest assured Shell the maker of the Polybutylene resin didn't suffer any where near as bad as the homeowners and installing plumbers. Shell at least stayed in business... Many of the plumbing companies were driven out of business. If you look back even on this forum you will see plumbers that are very negative towards PEX and frankly I'm surprised that no one has jumped in with a "The Sky is Falling" post. At the present time there are 2 companies that have had problems with their PEX systems. KITEC and ZURN are those companies and the problem was with the fittings not the tubing itself. With the price of copper as high as it is and PEX being so inexpensive and easy to install the copper pipe industry is losing its market share and is fighting back. In California the new code is allowing the installation of PEX. The war was fought on all fronts as the California Pipe Trades Consul was fighting it because of the skill level required for its installation they even made claims of chemicals leaching out of the PEX or, Contaminents in the ground water leaching through it. Interestingly enough copper in aggressive water conditions also fail the leaching tests as copper leaches into the water. One thing for sure the Pipe Trades Consul, The Copper Development Association, and Unions have a vested interest in this. Their claims have resulted in a conditional approval in California and they will do their best to keep making claims. What we see in these forums is someone making a post such as yours then a total lack of details... Please indulge me! Post that picture of the split PEX!