I'm not sure I understand the podium filter from your drawing, but I'm thinking that your "gravel bed" filter (aka, a bog filter) may end up being all the filtration you need. You could also do an under-gravel filtration system in the main part of the pond (such as the one described here:
https://www.pondtrademag.com/so-you...enance-free-system-for-clean-beautiful-water/).
And I'm with you on the Ozpond videos. Some great stuff there!
YShahar
As far as what I described as a “podium”-
It would be what I described as #2 in the top of this post. Basically a 36”Wx24”Dx6’H framed box (2x4’s & plywood?). This would be at the rim- outside and above the pool on the deep end width. This would contain and conceal any pump/s, pipes, and two 55gallon barrels modified as bioball filters. It would also act as a waterfall since it would be outside the pool and six feet higher.
If I ever build #3 (the “raised bed”channels) these would also be at the rim- outside and above the pool and be fed from #2 (“podium”). And they’d have a waterfall at each endpoint too. And plants grown in the gravel. I added drawings at the top of the post which attempt to visualize the description.
Maybe the main bog filter/gravel bed (#1) will be sufficient. Part of the three-prong approach I am aiming for is its flexibility. If I am too busy or broke, I can stick with #1(bog/gravel bed filter). And since that’s the hardest one to change, focusing well on that. #’s 2 & 3 are ways to add beauty as well as filtration & oxidation. And won’t take up swimming space since they’ll be outside the pool itself. And they can be added at any time.