Just curious David, where did you get your Coanda filters from? I bought one for my system from Bob Weir in Colorado. It really works well and has reduced maintenance to 1% of what is was previously. 
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Hello Martin,
I got them from Powerspout; if I recall correctly, they come from New Zealand—they’re the turbine manufacturer. And indeed, the Coanda screens are easy to maintain.
Still, one day I’d like to add an automatic cleaner on top of them.
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You also reminded me that I hadn’t posted anything else; here are a few photos of the installed pipes:
They are German-made pipes, and the seals are tested to withstand 6 bars of pressure; since I have less than 1 bar, I have plenty of margin. The run is about 220 meters long, consisting of two pipes with a 160mm outer diameter; the wall thickness is 6mm, if I recall correctly.
I also installed two 45mm conduits for the electrical wiring.
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Here is the connection to the upstream chamber (Coanda):
And the connection to the buried downstream chamber:
It is constructed using formwork blocks and is fully reinforced, as machinery drives over it.
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Just a quick point of clarification: the pipe is laid so that it always slopes downwards.
If there were a low point, a vent pipe would be needed to let air escape; however, with a consistent slope, the air vents naturally at the upstream end, so no vent pipe is required.
As you can see, I have securely stabilized the pipes using sand.
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Here are the two pico-turbines, installed in the underground chamber and tapped into the two pipes:
Water drains out at the bottom through an opening beneath a small bridge.
A stainless steel trap-style barrier prevents cold air from entering and noise from escaping.
I realize I don’t have a photo; I’ll take one at some point.
I am currently improving production using 3D printing and will show the progress later on.
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And where are your turbines, David. This downstream chamber does not make a clear picture for the machinery.
Haha, I was so hasty and pictures were already on the way.
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Oh darn, I didn’t leave enough suspense. 
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These mini Turgos look pretty nice. I visited the site you referenced and the price starts bellow 50 ths CZK. It’s a retail price of 10 000 kWh, what is cca yearly maximum production of the turbine. Nice
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One more question about design. Why two pipes? With the head of 6 meters and inner diameter 150 mm, single pipe flow is up to 170 l/s. This is far beyond capacity of both turbines and most probably beyond stream flow.
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That’s a good question; occasionally, the stream’s flow rate exceeds the capacity of the two turbines, so I had originally planned to install a third one someday.
However, that happens so rarely that I abandoned the idea—it’s already uncommon for both turbines to be running at full capacity.
I had calculated that a single 200mm pipe would suffice, but the necessary fittings were hard to find, and a meter of 200mm pipe actually cost more than two meters of 160mm pipe.
So, I played it safe, especially since the labor involved in laying two pipes versus just one was virtually the same.
In fact, I think that if I were to do the job again with what I know now, I would still install the same pipes.
I would also like to add that the site features a calculator that appears quite accurate and takes all variables into account, including pipe friction.
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