Steve is off building a pond in Texas this week so will be unavailable for comment.
He built his out of a heavy material and filled it with volcanic rock. It splattered too much and got to tottering in the strong winds of Central Oregon so he's back to the drawing board. Also I know he plans to have a higher turnover pump next time as well.
One of the guys in the Puget Sound Koi Club worked with stainless at his job,
so John and I got together and built my two. These are actually bakki shower types for my project as well as Steve's.
True TT's I had built out of plexi-glass. They're 5 foot tall, with drip trays and catch basin at the bottom plumbed with water return and airstones to air the water on return and send a column of air up against the downward flow of the water. The air exits out of escape holes just under the drip pan. I also had two built of those. I traded someone who runs a salt water aquarium store my 2 step kohaku from sakai-hiroshima that took tategoi award at the seattle show. I couldn't get him to quote me a price so I asked him what he'd take. I must admit it was a tough decision.
But if I can get one idea across in all my blabbering.....better to have a top quality pond with top quality water....then to have a top quality fish without the previous two!