Maximum, appears you are getting some great feedback.Let me add my 2 cents.I would have some real concern with the water level, 3 ft down in a pond this size is a huge percentage of water loss. If my math is correct and you have a water source at even 10 gpm you could replace 3 ft of water in 17.36 days. Fish load > Is 900 trout per acre a lot for your situation, I see stocking rates to 400 common but have not seen 900 to date.Your demand for DO will be great at this level when you ice over thus the thinking that a full pond level would increase your chance for winter survival. Not knowing what pump you have or which pore size on the FlexAir (several available)you have all I can suggest is to aerate at 1-2 PSI max this winter and perhaps with an on and off mode as with the success with BZ (if it works go with it)I would get the lines larger for the winter operation, 1/2 - 5/8 in the water is OK but 1 inch ID on the above ground portion would be better. Here is what works for us, look into a Koender/ Superior type freeze control unit as they can be adapted into any type of pump (I have some pics on our installation page)These units open at 12-14 psi backpressure and do a great job.Will your poly line handle the extreme cold, not sure as I only have experience to approx 20-30 F below zero and use Lowes silverline with no problem, Contact the manufactuer as they may have those specs.
