Cool vid, good find! I'm not sure it's more impressive than the slalom GF, lol, I really like that 1!
I've been giving the hoops some thought. I think rather than the wheel, rings of angel size would be good, ~5 or 6 inches. I've been trying to figure out a way so the rings have a rigid rod so it doesn't move in any water movement or if Althea bumps it. & it should be adjustable for height & spacing between rings. Not a permanent tank fixture but brought out at "show time", or as Althea will think of it, blood worm time. But you can still have a "non-circus" tank when you're not playing/training.
My idea involves a slightly longer than tank length of narrow wood (~1/2 to 1 inch wide) with notches at each end to fit on the rim. Holes would be drilled at intervals to fit the rods & allow for vertical adjustments, like a clothespin-like clip to hold it in place. Also extra holes can be drilled as she learns with more rings.
The narrow wood piece will still allow your arm & the all-important syringe'o'worms to fit in the lid opening (do you have a lid?).
When I had birds, 1 of their toys was golf ball whiffle balls, those might be too big & heavy...with too large holes for worms for Althea... but maybe if the worms were slightly thawed syringed inside a ping pong ball & frozen again or live blackworms. That would allow a longer period of play time & you could prepare several balls to keep in the freezer...
Still thinking. Fun stuff!