Originally Posted by BargainFittings
I advise they be put in the bottom 3rd of the smallest batch size you do. 2-3 inches above your drain will work.
I have my copper return arm attached to the top of my immersion chiller (I used a couple strands of copper wire to fix the two together). I found it takes a little trial and error to find the angle that generates the best whirlpool...and the angle can make a huge difference.
Not from experience, but I heard concerns somewhere about the return port on the bottom as it relates to whirlpool chilling. Basically, if the return port is too close to the outlet port, you may recirculate the same wort and slow down chilling efficiency. Naturally, if you are not whirlpool chilling, this is def a non-issue.