Dad the grey pipe on the left is linked to the washing machine, it got loose and leaked. How do I stop it happening again?
(reddthat.com)
Bonus tip for anyone diy-ing plumbing: Chances are decent that you won't get it all 100 percent right the first time. Pick up a water sensor for $20 at the hardware store and put it under your work when done. That way if something leaks you'll know right away instead of when mold and water damage happen.