Is a super low GPM pump better than a higher one?

[steppinthrax]

So here's the deal, I got a new filter (filter details in signature). When I installed the new filter coincidentally my pool pump blew (posted a thread about this a while back). So while I ordered a new pump I placed a shallow well pump (3/4 hp) 9.2 gpm pump as a substitute. This pump was sooo low power that it didn't even register PSI on my filter gauge. It took around a week until the pump came in, but I noticed my pool water was crystal clear. I mean so clear you could spot some imperfections within the liner.

I then got my motor (1hp 60gpm) and installed this. Right when I powered the pump up I noticed a cloudy mess shot out from the discharge line. It was like a cloudy discharge that came from the filter. The water overall got a little cloudy (but not too much). The gauge was registering around 10PSI.

So my theory is in a low power pump the water moves very slow through the sand and filters better. But in a high powered pump it goes through so fast that it can even take material with it out the filter? The filter is in great condition I put new sand and the laterals were perfect. What causes these anomalies!!!!!

 

[jblizzle]

Certainly lower flow filters better, that is one advantage of the 2 speed and VS pumps. The other is lower running costs.

But, you still need to have enough flow for adequate circulation of chemicals and under 10gpm might be pushing it. That is also too low for my SWG flow switch. So there is a trade off.

 

[steppinthrax]

Certainly lower flow filters better, that is one advantage of the 2 speed and VS pumps. The other is lower running costs.

But, you still need to have enough flow for adequate circulation of chemicals and under 10gpm might be pushing it. That is also too low for my SWG flow switch. So there is a trade off.

OK,

If that is the case. Is there some sort of "Variable Resister" I can splice between my pump so that I can "slow" the pump down a little? I'm thinking some of those Light dimmers.

 

[JasonLion]

Not really. There are motor speed controllers, but they require special "inverter rated" motors.

 

[happyheathen]

I have seen 2 motor controllers in my life - both rated for fractional hp only (exhaust fan in kitchen, and a cute little box you plugged you old drill into, and, presto! you now have one of the fancy variable speed drills. Yes, the was circa 1960.

I wouldn't even think about trying it with a multi-hp pool motor, even one rated for it - too much current.