How to make using less then a full $10 roll of 4 mil plastic sheeting, old scrap wood, some extra rope I had laying around, and a working pool pump i found in a neighbors trash (missing the filter which was broken). I used scrap pieces of rubber pond liner to make the bottom softer but is not required.
This is a Solar Hot tub, Sun Heated only version, as I just wanted to test the concept… In the future I will add either a homemade wood burning or propane gas grill style powered heating element.
You could use a small pond pump if you do not have a pool pump. As long as the water keeps moving and you add a few tablespoons of chlorine or bleach the water will stay clear.