This is my new setup so far, I want to use ceder planks for the sides, covered with layers of plastic,

[Tyson]

are you talking about making a large, indoor pond type structure, using pond liner?

Pit will have a plastic sheeting inside in case of splashing, but there will be one third ground, one third plants, and 2 foot circular pound and twisty waterfall will make up the final third. It will be a little tropical paradise, I'm even going to put tiny outdoor speakers on the back, so I can put rain noises, and once in a while ill even pipe in tiki room for video taking lol