I'm building a solar water heater with solar vacuum tubes, For my 4' pool. I have nine 20" solar vacuum tubes. Which I intend to fix 3 each into 3 separate plastic tubes. This device will either percolate (like a coffee maker), or I can use a small pump, to pump water to the lower segment, spilling or 'tubing' back into the pool from the top.
I'm needing a (clear non-UV-resistant) plastic tube. That can withstand boiling water and the steam a the top. The dimensions need to be greater than 2.5" inside diameter, available in 4-6 foot segments.
I've seen acrylic tubes that can withstand 180 degrees F, but need 212-300'ish or more, and an unknown pressure if I percolate. Aiming less than $100.