We were predicting fish winterkills back in early February due to heavy extended snow cover on northern ponds.
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Main=28519&Number=365230#Post365230

Dissolved oxygen dropped to 2 mg/L (ppm) in my pond back in mid January and I started aerating several hours a day about 3 to 4 hrs and kept the DO high enough so fish survived (2-4ppm). In comparison I measured DO in a 20ac reservoir with 12" of clear ice on Mar 11. Wind had kept snow mostly blown off the ice. DO on this 8ft deep reservoir was 9.5 top to bottom. Clear ice with little snow cover makes a big difference in the amount of DO under the ice.

Discussing winter aeration:
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Main=28010&Number=365379#Post365379

Water testing under the ice.
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Main=28520&Number=365466#Post365466


Last edited by Bill Cody; 03/15/14 08:03 PM.
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