I have read several times on the forum that well water has no dissolved oxygen in it. I had the opportunity to visit Gavin's Point national fish hatchery in South Dakota last summer and noticed something that made me wonder if some well water may have significant amounts of DO. They had a run that was about three feet wide and 50 feet long with Rainbow trout in it. At one end there was a pipe pumping water into the run at high volume. It was sub surface and no turbulence on the surface or airation was going on. I asked the fisheries biologist where the water was coming from and he said it was well water and had not been processed or airated.

If you Google DO in well water, there are several publications discussing the issue, and it sounds like there can be significant DO in well water depending on the well.

Just wondering if a person could measure the DO in the well water to see if it needed airation prior to being pumped into a pond?