Pond Boss Forums MANAGING AN EXISTING POND Evaluating and adjusting fish populations YP Progress

This is awesome, and thanks to others for chiming in and explaining it better than I could.

My original thought was the origin of this thread, how to get YP to do well in a more southern pond. I think my point was that the YP can tolerate warmer temps than they get credit for, if they have a zone of cooler water to go to. Now, I don't know if that is strictly a hot/cold thing for their body and stress related to heat, or if it is truly dissolved oxygen levels they are seeking. If it is truly dissolved oxygen then in theory you could maximize aeration even in a warmer pond and they would do well. However I feel that the texas folks would say that at 86 or 90 degree surface temps they could maximize their aeration and DO would max out at 7.6 (per chart above) That is adequate for YP survival yet northern strain YP would still die so heat stress must be still independent of DO stress.

Banking on that assumption, and that my pond is shallow (lucky to hit 10' at full pool) I'm trying to preserve as much cool water as possible for them come the dog days of August. I can add 55 degree well water on a timer but only can do this when my house water needs are zero (while everyone is sleeping) and I can also hope that turning over the surface water by aeration at night will somehow allow the cool air to mix better with the warm water.

(that sounds like a theory as is so aptly pointed out above, when we aerate at night are we just mixing the hot water at the surface from the day's heat and pushing it down, or are we actually exposing a whole bunch of water to the air for heat loss by convection by turning on the big slow water circulation process via air lift - aeration. In my pond I can turn over the whole pond in about 24 hours so the 8 hours of night aeration only does convection to about 1/3 of the total water)

In my shallow pond the temp differential even with night time aeration from top to bottom is not much, so the DO readings from top to bottom probably are not that different.