This whole pool thing is totally new to me, so people forgive me for asking such a basic question ...how does the 1000gph filter work? Does it have a timer? Do I just plug it in when I want it to run? I'm planing on using it with the saltwater system, which I think has a timer. Should I just run the filter whenever someone is not in the pool or would this be too much? The pool I think we are going to get is the 15x48 metal pool. Also, is this filter any good? I've read a lot of reviews about the filters that come with the pool can't keep up. Thanks so much!!