I'm needing a method of collecting the water from the end of my NFT channels so it can return to the system. Easier said then done. I found a window box planter but it is a little too short and is made of mystery plastic (no markings). My other option is to use vinyl gutters to collect the water. They are inexpensive as well. I know that most vinyl is not food safe. Can I paint it with something to seal it maybe?