This is a close up view of the gutter - note all the white filament - they are roots. They appeared the 2nd week after planting. They seem to be just fine and healthy. I make no effort to aerate the water, although I do cover the end that is exposed to the sun so it won't become engorged with algae.

I placed the gutter East West rather than North South, which I should have. That would have given both sides some sun. But there are trees to contend with in this dog pen too, so it will work for this season.