@brokensword - see you're in the first camp! I can do lots of creative things, but if it requires accuracy and precision, I'm out. I sewed Halloween costumes for my kids for many years, but I would never had attempted to make them something they actually had to wear!
We definitely took a risk just building our bog. We were kind of at the beginning of the bog revolution (lead by
@addy1 - haha!) and were able of find very little in the way of information or inspiration when it came to "how to". (Don't ask me how I never managed to stumble on THIS forum!) So we had to really reason our way through the whole process and understand how this wasn't a "bog" like in nature, but shared some of the same functionality.
All we heard from experienced long time pond builders was "that will NEVER work". Aquascape was just starting to tinker with bogs at that time for home ponds so we would hear the word "wetland filter" from time to time on a pond tour, but never actually saw one built from start to finish until we built ours. We were just kind of putting ideas together as we went along. We did use centipedes and snorkels though - for us there was a level of comfort in using a tested product versus putting something together on our own. Now I would have a lot more confidence in that process. But for the amount of enjoyment we get out of our pond, I don't regret a single penny we spent.
Now I love to go back and tell those "experienced" pond people what they DON'T know about constructed wetland filters. And don't even get me started on my negative edge -
I actually found info re a bog from a professional pond builder in Ga. There was a write up and since I like plants, a filter made from them was right up my alley. Didn't really know much re cycling or anything (funny, too, since I've had aquariums since I was a kid; just followed whatever my dad did and must have absorbed it by osmosis without really knowing what I was doing!) and the only gripe I had with the instructions was there was no obvious statement re slopping the bog walls. Hence, I dug straight down. Other than that, though, this guy must also have been on the leading edge of wetland filtration. He used large stones graduating to smaller until a top layer of pea gravel; that's why I did mine as I did. And as far as I can figure, I've seen no one else mention using 4" drain pipe. Most are using the 1-1/2 or 2" rigid pvc. But if you think about it, the 4" will slow the water and provide more 'muck buildup' time, as an Aquablox does. And it was cheap to build, other than jury-rigging the vault and vertical chute. I actually looked at what he suggested--12" corrugated plastic drain pipe but it was $75 minimum and I figured I could mimic for a lot less. Might sound wonky, but since I had all these empty plastic cat litter pails (and wouldn't you know? My extra sump pump fit nicely inside!), I cut bottoms out and stacked them until I had my 40" of height. So you can see, I don't overpay, hey?
I've visited Koiphen (still do, but just for kicks) and it's pretty amazing how blinded they are relative to what can be done. I guess, according to them, there's really only one way to have a koi pond. I tend to 'want it all' so until I run into that immoveable object, this unstoppable force will just keep going!
Why exactly did you shy away from the tried and true of canister, barrel, drum, RDI, settling pools, multiple stage filter systems that so many koi videos promote? I shake my head when I see these, both at the probable cost as well as space/maintenance they consume. But, many like to tinker and that's probably part of the allure of ponding for them. I'd rather tweak and sit back and relax, once the initial setup is up and running. Gives me more time to figure out underwater video systems, water-level video ideas, and even an aerial view (haven't mastered my new drone yet, but maybe next summer!).
And I hear you; you're still ALSO in a category of your own as most would hire much of what you did out and then just relax. I think ponding almost necessitates hands-on involvement to get the most out of the experience. Like many endeavors, you only get back what you put in.
Also, have you fully finished with koi? I know you lost all but one. I found since I got the 'bug', it's hard to now stop. I decided there wasn't enough color variety in just goldfish so I tried my hand at koi. It was my main motivator for the expansion as I lost one of my first 3 over winter and figured I'd broken the envelope.