I use pre-coiled airline tubing from WalMart. 50’ is around $7.00 and is found in their hardware department. The bright yellow color is inert and will not impact your livestock. Also, the inside diameter is perfect for this project! ¼” ID is ideal but you can go up to a 3/8” ID if you prefer. Remember, the unit is sealed and cannot be cleaned once finished!
Please note that you’ll have to cut the brass air pressure fittings off both ends of the coils prior to dropping into the PVC cylinder! The bottom cut-end of the coils simply rests at the bottom of the cylinder, unattached to anything. The top cut-end of the coils will be attached later to the nipple fitting attached to the lid.
