Just to add to an old thread on the challenges f trout. I have done everything wrong nd learned slowly what must be in lace for trout to succeed, Of course, Cecil and Theo have been real helpful along the way.
in 2003 I lost 200 17" rainbows in early July in middle Michigan, after leaving the aerator running 24/7 and thereby super-heating the water to 75 degrees. Water just doesn't hold much O2 above 70. Trout were swimming in circles a the surface with fins exposed. We even found a dozen had gone psycho and jumped out of the pond and their intact skeletons were found on the shore.
WE have a 1/3 acre 50 yr. pond that was dredged about 3 yrs. back to add depth (12 ft. in some places- now) still not that deep. We re-stocked last Spring and made it all the way through the summer in good health!
Here was the formula- we had to have a new well drilled (just a little 2" steel pipe well). Our old artesian well was producing 15gpm of 48 degree water year round, all for free! Taht wasn't enough water. The new aretesian well hardly gave 4 gpm so we added a 1/2 hp well pump and it added another 20+ gpm, dropping 3 ft. to the water from a pvc pipe.
The other "trick" - our best solution was to add a thermostat (ACF Greenhouse supply) 220v thermostat that turns on and off the aerator. In the winter it is set to go on (and stay on) when the temps dip below 35 degrees. Keeps it ice free all winter. Turns OFF at 38.
In early summer, it is set to go on (aerate) when the temp drops to 65 and then OFF at 68. This is critical, as the aerator only goes on at night, when the evening temps dip. then you not only get aeration, you get a cooling effect. Since this is an automated situation, on hot nights of 75,80 and more, the pond sits still, and does not warm up at all. In middle Michigan, we looked at weather history for every day from June through September for 4 years backward. Only 1/4 of the nights stayed hot, but hat is enough to warm things up to much.
Short scoop - never pump well water to the bottom without aerating first. #2- big volume of incoming cold water is essential for trout success through the summer and 3rd- aerate whenever possible, but never when the air temp is over 70 (unless it is spring and you want to raise temps).
