25k Gal Pool, building myself, need returns, pump sizing opinions

[Spiffdandy]

I am building a 25k gal pool in the philippines, as there is no qualified pool builders in that area. For this 25k gal pool, it seems that 2 skimmers are adequate. I have heard differing opinions on the amount of returns to install. Some Pool experts have said that 2 each 1 1/2" pipe size returns are enough. Others say that 6 or 8 returns are better to create a smoother flow thru the Sand Filter. My current plan is to purchase 2 of these builder kits WaterWay Renegade Vinyl Liner Skimmer - Builder's Pack - PoolSupplies.com which would have a total of 6 each, 1" returns, which 3 each of these returns will be plumbed in to two 1 1/2" separate lines (did that make sense?), meaning 2 each 1 1/2" lines going out to 6 returns spliced in to 1 1/2" piping. Of course the less penetrations thru the pool wall means the less chances for leakage and piping issues later. Also planned on putting one of the extra main drain connections stubbed thru the wall and capped for now for future water slide installation. Plan on using a 1 HP circ pump. Comments are welcome !

Regards,

Spiffdandy

 

[Nectarologist]

I have the same skimmers. I love them. I owned an above ground pool with Waterways equipment and skimmer. these are huge compared to my AG pool, haha. It's a good thing too b/c where I live now there are two oak trees hovering above the pool (tons of acorns but the skimmers scoop em right up). I have essentially 3 returns. 1 on the wall and 1 at the stairs and 1 at my roman end bench. For the stairs and bench there is a return for each that splits into 2. Looking at the pool it looks like 5 but it's really 3 runs coming from the filter. I personally think you don't need that many but I don't have any other reason besides I've known people who have had two returns and they never had an issue. I worked in pool service yrs ago and saw plenty of pools that size with only two returns. I've seen some really old concrete pools with one return. No issue except that when heating it's only going to that one area and spreading out from there. I hope someone can give you better reasoning for an answer. Good luck!

 

[Casey]

I'd go with the very minimum of 4 returns. The more the better in the way of circulation. You don't want dead spots. If you can upgrade your lines to 2" pvc, that would be better than the 1.5" lines.

 

[Spiffdandy]

Thanks Casey, so go with 2" for the return lines.....and "T" off of them for each of the 1" return feeds? (6 total) ?

 

[duraleigh]

I think Casey may be thinking of suction lines. 1.5 inch lines are gracious plenty for returns and, depending on your plumbing, I would branch them down to 1" lines traveling to the actual fitting.

In a normal system, you need to create SOME resistance on the pressure side so narrow your lines down.

 

[Casey]

Oops sorry. I may have! Thanks for catching my mistake Dave!

 

[mas985]

If there are 4 independent parallel runs from pump to pool, then 1.5" is more than enough. If there is one run with 4 branches at the pool, then I would say 1.5" is way too small and I would go with at least a 2" return line. It depends on how it will be plumbed.

But I wouldn't have 4 parallel runs as that may have too little head loss. I would go with one 2" line spit at the pool.

 

[Casey]

I'd listen to Mark. He knows his stuff.

 

[atttech-2]

I would go with one 2" line spit at the pool.

That is what my PB did one 2" split into 4, 1.5" returns at the pool that are nearly equal in length.