pvc piping?

[vettester]

Polyvinyl chloride - Wikipedia, the free encyclopedia
You might want to skip down to the health and safety section and come to your own conclusions.

It looks like Polypropylene would be an even a better choice that Polyethylene from a health point of view.

"Polypropylene (PP) is a robust plastic that is heat resistant, considered highly safe for human use. Due to its high heat tolerance, Polypropylene is unlikely to leach even when exposed to warm or hot water. This plastic is approved by the FDA for use with food and beverage storage. Polypropylene plastics can be re-used safely and with hot beverages."

Anyway, I'm just getting started in this hydro thing and don't feel like taking a chance on any plastics leaching into my organic and/or heirloom tomatoes.
Thanks for the reply.