I checked DO yesterday in the AM and PM I don't know what to think...
It was 4 ppm in the AM and 4 in the PM. The following readings stayed the same for both AM and PM...pH-7, TDS-50 ppm, and clarity-18". I have read that 4 ppm is reason for concern.
With my lack of water chemistry experience, the only things I can think that would cause this is too many pounds of fish in the pond or my DO kit is wrong (Dissolved Oxygen CHEMets Water Test Kit).
I have an estimated 350-400 pounds of fish in my 1/4 acre pond. And, the aeration should be turning the pond over about 4 times a day, running from 11pm to 8am. HSB are around 1-1/2 pounds, HBG are 1/2 pound. There's no submerged plant-life, little to no FA, but the banks are solid in with grasses, some emergent plants along with about 100 sq feet of water hyacinths.
I'm open too everyone's thoughts. Is it time to remove some fish?