Catchment system for leaks at plumbing joints?

How does that song go...
When the shark bites. Into pex dear, Plumbing leaks Go away
When the Shark Bites Into pex dear, Dry times are hear to stay.


The only "Catchment" system I know of is a larger pipel. FOr example you can put a 2" pVC over the 1/2 inch PEX and if it leaks, the PVC is drained to under the RV.. IN fact that is how some pipelines are built and all should be

With a pipe inside a pipe (inside a pipe) so if one bursts, the next size up plays Catch.