Okay, I seem to be getting more confused here.

First things first -- I have at least 2" piping, if that helps (actually, the OD seems to be around 2 1/2 but I'm guessing we're talking ID). The filter PSI is 30 and the pool is about 11,000 gallons. I have a salt chlorinator if that means anything.

For the last month or so I've been running three hours in the morning and three hours in the afternoon and this works fine for solar and skimming. Based on the information here I've tried lowering it now to 2 and 2 (for a total of 4) as that's plenty for solar. Side note: in the winter I've always run the pump for only 5 hours (I read somewhere you didn't need to run it as much in the winter) and this was never a problem but now that I have solar I'll probably run it more (paradoxically).

Leaving aside all the controversy about piping and such, is there any way I would know (visually or otherwise) if I run the pump too little? I mean, will the water be too cloudy, or the balance get off or some other symptom that will tell me I need to increase the pump time?

As we're on a fixed income (and running this huge pump is *very* expensive) it would be really nice if I could run this as little as possible.