The pond was not thermally stratified in 2015 nor 2016 when the measurements were collected. The planktonic algae bloom in 2016 is consuming lots of DO during the night(algae respiration) so when the DO was measured early morning it is quite low which no doubt stresses the trout. They are barely surviving at 4ppm. Trout are stressed at DO below 5. The cooler temps in the 40's help reduce the DO stress to the trout. Several cloudy no wind days will result in low daylight DO production. If you have a trout kill this fall-winter it will be due to the 2016 plankton bloom if it persists.

Last edited by Bill Cody; 10/04/16 03:31 PM.

Keep This Forum Viable, Read Pond Boss Magazine -
America's Journal of Pond Management