Francis, I only used rebar for 30 days because I quickly realized that it was leaving shadows on my iron, and I listened to the collective years of experience here on this Forum, and quickly moved forward to using the two plate systems shown above.
ALL of my anodes are now Stainless Steel. (10 to 12/14 gauge).
The plates came from a local source a couple of counties away... and is SUPER heavy duty non-magnetic stainless.
I had the plates cut to spec by a local machine shop, with a Plasma cutter....
Just last year, I sold my excess plates to another WAGS member at the Convention, as I moved froward to 360° coverage fairly quickly.
The principle of of Electrolysis works as Direct line of Sight.... so the surface area of the anode(s) should be AT LEAST as Wide and High as the piece being cleaned.
My SS Barrel came from Ohio... and was acquired for me by another WAGS member who shipped it to me.
My SS circles came from North Carolina.... once again from a WAGS member who found them in a scrap yard down there, and another WAGS member who picked them up and transported them slightly further north, where I picked them up from there !
(you see the theme here is..... my WAGS buddies have been tremendously helpful, because in my area, finding SS is difficult. ;) ;)
I also have two small SS barrels not yet in use, to clean 'smalls'.... from my WAGS buddy out in Eastern Pa (where there are still a few 'real' scrap yards)
Also, most of my hangers and all of my connecting hardware is Stainless Steel,,, from washers, to wing nuts, to flat slotted, to nuts to bolts, including the threaded rods that you see.
Clean solid connections are critical, and SS hardware allows me to maintain solid, clean connections over time, with minimal maintenance.