The lid or "cap" should be drilled to accomodate the two fitings, intake and output. No other modifications are necessary. A secure, watertight fit is essential between the fittings.
The bottom or base of the unit is sealed permanently to the cylinder. Diameters will vary depending on the size you decide to construct.
There are 2 fittings needed. Red indicates the INPUT side. Here, you attach the tubing to be coiled down the inside diameter of your cylinder. Match the fittings to the size of the tubing you select. I prefer 3/8ths. I.D. now over 1/4". BLUE represents the OUTPUT fittings. Nothing is attached here, allowing the internal water pressure to force the processed water back into your sump or display tank. There are no moving parts, nothing complicated nor any special knowledge needed other than the tools and materials needed for assembly.
