Major redesign on the tubes, thank god I did!! The previous design had 4nr 2mm holes every 1cm… I decided (because the drill packed up…) to instead switch to notches cut into the tubing, which allowed for more contact between the soil and the nutrient solution and air.
Stupidly I started leveling out some of this micro vineyard, where the water drains from quickest, as I am installing some more over the course of the day… They are painstaking work to make, I will get a picture of the next one I make. This is them in position now:
The next two are the difference half an hour has made, with a more compact soil, it does tend to drain a lot slower now… 30 mins to drop the standing water by about 2 inches though, a further half hour for all tubes to have been evacuated, as above if I had taken picture before leveling it.
Below to left: After half hour of watering. Below to right: After another half hour.