I HAVE A 1/4 ACRE POND ITS 7'DEEP. IT IS NOT SPRING FED. IT LOSES ABOUT 3' OF WATER BETWEEN JULY AND JANUARY. WHEN THE MOUNTAIN HOLLOW RUN I RAN A PIPE TO FEED THE POND IT WORKS GREAT. I HAVE CATFISH, BASS AND BLUE GILL. ONCE THE PIPE RUN WATER TO THE POND IT FILL UP OVER NIGHT BUT I LET THE WATER KEEP COMING UNTIL THE HOLLOWS DRY UP, THIS COULD GO ON UNTIL JULY. I USE TWO RING TYPE AIRATORS BUT DID NOT TURN THEM ON UNTIL JUST A DAY OR SO AGO. ABOUT 15 CAT FISH AND 2 BASS AND SOME BLUE GILL HAVE DIED IN A COUPLE DAYS. THE PH IS REALLY LOW. WHAT AM I DOING WRONG HOW CAN I CORRECT THIS PROBLEM ITS HAPPEN TWICE NOW
THANK YOU
CHRIS

Did the die offs start before aeration, or after? How was the weather the days leading up to the die off?

I would think your water had already turned over, so that acidic, anoxic water was no longer in the bottom half of the pond....If your aeration diffusers are set deep, and your pond was iced over, you may have supercooled the pond...we need to know more info to offer better opinions...Honestly though, it sounds just like a mid summer aeration start up that mixes the poisonous bottom water into the rest of the water and kills fish.