On a "standard" pump system (sand filter) with a separate Polaris pump installed can you operate (safely) the Polaris pump without having the main system pump on. The Polaris pump draws water from the line returning water to the pool from the main filter. I have what is referred to as a flooded system. There are times when the main pump (timer) has cut-off while I am not at home and happen to run the Polaris pump for cleaning. I just want to ensure there won't be any problems. It doesn't appear to be damaging or straining the system when this has occurred. In fact, I may be seeing better service from my Polaris since it is operating unaffected from the flow of the normal filtering system.