Bob - thats some interesting data and something I will have to consider when I run a final model.

What kind of pond is it? does it contain fish or does it just act as a 24/7 water pump.

I know in my experience people tend to just run water features when they are likely to be around them but if you have a need to filter the system then obviously you need to run 24/7? What are your reasons for running 24/7?