If you could put a heater in the system and could keep the water at warmer temp, would you?
I know the risk of disease is there when using water from a pond, but if the fish will be released into that BOW, then if you used water from that BOW to fill your RAS at the start (if using a filter system rather than a flow thru system) wouldn't that jump start the filter system?
Even with a flow thru system I think I have a way so you could heat the water..........
