Piping reqts for pump

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What 5x rule are you talking about?
What piping requirements are you talking about?

If you mean the pipe going into the pump needs to straight for 5x the diameter of the inlet, this is wrong.

The pipe in front of the pump has little bearing on cavitation or any other issues with pumps. It is something that is recommended in the water distribution industry where the pumps are much larger and much more prone to cavitation and they don't use a pump basket so the flow into the impeller is directly related to the plumbing attached to the impeller inlet.

A residential pool pump has a pump basket which completely changes the fluid dynamics into the impeller inlet so the plumbing ahead of the basket has little impact to the flow dynamics other than head loss. Plus the turbulence in a typical pump basket overwhelms any benefit that a straight piece of pipe might have. Although some pump manufactures continue to recommend it for residential pool pumps, there is little evidence that it makes any difference at all. Most installers of pumps ignore this recommendation without any deleterious effects whatsoever. I would make the straight piece as long as you can but don't get overly concerned about it and don't add any extra fittings to get a longer piece either.

If you could post a picture of your pad, and fill out your signature, that would help.
 
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strange I was posting on a different thread and it looks messed up. Someone replaced their pump and filter and another user commented on their line coming to the pump. I was agreeing on the 5x rule on the input to the pump but was asking for the pressure side of the pump, are there any rules for pipe length?
 
See post #2 above for the suction side inlet length.

For the pressure side, also see post #2, for the update to your signature and pictures of your pad.

Finally, post the pre-filter (make/model) that you are considering. And, why are you considering a pre-filter. It is likely un-necessary. You may be better off with disposable hairnets in your skimmer baskets.
 
i have the skimmer socks on the pool and spa skimmers, they do help. I also have a leaf vac canaster before the pump basket. I need a much longer sock for that one, but I do collect alot in that basket, guessing from the floor drains (in floor cleaners) but my problem comes more from trees around me. We have 3 mesquite trees around our backyard and they do drop slot of small needles that do make it to my filters, and they are a super pain to clean out of the pleats of the filters. So I'm thinking if I put a prefilter, 1 of those cyclone types and can catch those needles It might help my filter washing.
 
Yes. I get 100 for less than $10 (Amazon). Change them out once a week typically.
 

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