Does the 2nd intake on Intex pool actually filter anything..?

[ninjajim4]

I've been trying to find some information about the actual function of the second intake outside of supplying enough water flow to the pump. Have seen plenty of threads that say it's just for safety purposes, or else talk about plugging up the second intake to make the skimmer work.

I'm in the position now where my skimmer doesn't work well without the flow reducer on the other intake. Ideally both would work with neither restricted but it doesn't seem to be the case so I leave the flow reducer off since the pool is covered most days and skimming is not effective with it on, with the hope that more of the sub-surface stuff is getting filtered by the other intake. I don't have any sense of whether or not this is true. I don't have any flow/pressure issues to the pump whether one intake is restricted or not.

So my question is, should I continue to do this or should I not bother and let the skimmer do its thing whether covered up or not? Will the skimmer's submerged basket still get the sub-surface stuff? Or do neither really accomplish this and I just need to focus on vacuuming?

 

[mas985]

If it is just a port in the wall, then it really isn't doing much. It does filter the water but most debris that is large enough to be filtered by a typical pool filter is too large to remain suspended in the pool water. It will float or sink.

With an Intex pump, I am surprised you would need a second port. They are not very powerful.

 

[ninjajim4]

I have heard the main reason for the second port is liability issues, e.g. a small child could get stuck against a single intake and trapped by the suction/resulting vacuum. From a physics perspective, it's two 1.25" hoses connecting to a 1.5" hose so a second intake adds only .25" diameter of additional total flow. I don't see how it could make much difference and I think the ones that do have issues blocking the second intake off must have some flow issue with their skimmers.

When I had the smaller 1500GPH pump with the inline heat pump and the skimmer, I noticed a lot of sub-surface debris floating around. There is certainly a lot less now that i've upgraded to the 3000GPH, but again, I don't know if my swapping the reducer in/out is helping at all or not. I guess I will have to trial and error it. It's annoying/disappointing to think I have to pick either surface skimming or sub-surface and can't have both working at once, and it also means more effort since I find myself uncovering the pool when it's not in use just to give the skimmer some working time.

 

[mas985]

You could put a check valve on the secondary line. It would only open fully if the skimmer port was blocked and/or restricted.

 

[kellyfair]

I usually kept my second inlet either off (with a valve) or partially open to make the skimmer work better. I did like leaving it partially open since it was positioned lower in the pool and if the water level ever dipped below the skimmer, my pump wouldn’t go dry. That was more for my paranoia than anything - I only have one inlet now and my water level has never dropped too low.

 

[ninjajim4]

I usually kept my second inlet either off (with a valve) or partially open to make the skimmer work better. I did like leaving it partially open since it was positioned lower in the pool and if the water level ever dipped below the skimmer, my pump wouldn’t go dry. That was more for my paranoia than anything - I only have one inlet now and my water level has never dropped too low.

Sounds no one uses or expects the second inlet to do much with regard to filtering. Still, I like this idea of putting a valve on so that hopefully both inlets can do some functional work