We are in the design process for a gunite/plaster pool with a spa and trying to decide on sanitation methods. I’ve owned chlorine pools, and I have had an SWG pool 10 years ago. We did have clean water with it, but the limestone coping eroded noticeably. I would like to know if UV treatment would reduce chlorine significantly and eliminate limestone erosion. My contractor recommends against SWG so I’m looking for more info. Thanks
Trying to Decide UV or SWG?
- Thread starter LWeber4
- Start date
- Jun 24, 2021
- 15,940
- Pool Size
- 29000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-60 Plus
I am PoolStored. I was pool stored for $1500, including a new UV system. After learning here, I tore the system out and trashed a $1000 UV system. Then I created my username.
It will not reduce chlorine use. It is UV...the very thing that consumes chlorine. Save your money.
www.troublefreepool.com
The limestone issue is the quality/type of the stone, not the SWCG. Lots of threads here. Search "stone swg" or "salt water stone" Here is one good thread. Natural Rock Damage with SWCG
Avoid the UV. Get the SWCG. Enjoy the pool.
It will not reduce chlorine use. It is UV...the very thing that consumes chlorine. Save your money.
UV Systems - Further Reading
www.troublefreepool.com
The limestone issue is the quality/type of the stone, not the SWCG. Lots of threads here. Search "stone swg" or "salt water stone" Here is one good thread. Natural Rock Damage with SWCG
Avoid the UV. Get the SWCG. Enjoy the pool.
L,
Your cheap Texas Limestone will erode with or without a SWCG...
We do not recommend UV systems except on indoor pools..
That said, it is your pool and you should get what you want.
Thanks,
Jim R.
Your cheap Texas Limestone will erode with or without a SWCG...
We do not recommend UV systems except on indoor pools..
That said, it is your pool and you should get what you want.
Thanks,
Jim R.
The Texas sun will provide more UV than any light bulb ever will. UV is not a replacement for chlorine.
Some Texas limestone/flagstone is junk and will disintegrate regardless of what water touches it; a SWCG didn't cause that. The coping around my pool also looks like garbage in some places because it's TX limestone/flagstone. It's looked that way for years. Many years before it ever had a SWCG installed.
Some Texas limestone/flagstone is junk and will disintegrate regardless of what water touches it; a SWCG didn't cause that. The coping around my pool also looks like garbage in some places because it's TX limestone/flagstone. It's looked that way for years. Many years before it ever had a SWCG installed.
Unless any device deploys a tent over the pool, your battle is with FC loss due to UV. Adding more UV loss is just plain silly. The residential units don't equate to much more than a light bulb, but still.
A SWG will combat UV loss by adding FC on your behalf.
A UV device will not.
A SWG will combat UV loss by adding FC on your behalf.
A UV device will not.
- Jan 3, 2023
- 344
- Pool Size
- 9500
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
I'm with poolstored. Pulled my UV system 6 weeks after the pool was built. Sitting in storage trying to sell it to anyone who wants it. That and a chlorinator I pulled too.
Regarless of what your builder says SWCG is the absolute right choice. You won't regret it.
Regarless of what your builder says SWCG is the absolute right choice. You won't regret it.
Thanks for the fast responses! I’ve been researching SWCG all morning and I’m not finding any negatives except upfront cost. For what the pool will cost overall, adding an SWCG system is so minimal as to be invisible! I’m going with the SWCG system. I have read the limestone erosion is more a function of ph than anything else (besides natural erosion). We’re looking at lueders for coping which I understand is harder than regular white Texas limestone. Thanks again for this information.
- Apr 10, 2018
- 6,323
- Pool Size
- 18375
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
Make sure the builder selects a SWG rated for al least 2x the pool volume.
- Jun 1, 2018
- 16,012
- Pool Size
- 26000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
Here’s a couple good links as you start your journey 
www.troublefreepool.com
www.troublefreepool.com
Pool Care Basics
Feel free to post up your build & equipment proposals & you’ll get lots of help here to help you select the best options.
How to select pool equipment - Further Reading
www.troublefreepool.com
Construction Best Practices - Further Reading
www.troublefreepool.com
Feel free to post up your build & equipment proposals & you’ll get lots of help here to help you select the best options.
My personal position on UV systems is that they are good at what they are designed to do, but having said that, I don't know of ANY residential pool that would benefit from UV (or ozone, for that matter). My recommendation would be to install a chlorine injection pump and find a good supplier of "bulk" sodium hypochlorite.
And progress pics. The more eyes on your project, the better it will be. Folks spotted all kinds of details I missed while I was focused on frying bigger fish.
I read the OP and immediately looked for location before reading any more replies. When a post mentions contractor recommends against SWG, it is a contractor based in Texas the majority of the time.
You'll have to ask your fellow Texans here on the forum. Over the years, it's just something that sticks out with contractors in Texas. Here in NC, I knew nothing about pools in 2006 and my pool contractor put in a SWG. Lucky for me.
It's just a bizarre pool builder myth/belief. Maybe they want to sell pool care services and know SWCGs put a damper on that. Primarily I think it's because they're completely clueless about water chemistry.
Florida has it's own pool builder quirk where they only install the smallest filter humanly possible.
Florida has it's own pool builder quirk where they only install the smallest filter humanly possible.
UV systems work pretty well for drinking water. No sunshine inside the pipes so high-intensity UV light can do a job. For an outdoor pool, sunlight is free 
. Also, even a high-intensity UV system won’t kill filamentous algae or any algae that’s attached and not free-swimming in the water, so you still need adequate chlorine for that, UV or not. Go SWG and you’ll never look back.
. Also, even a high-intensity UV system won’t kill filamentous algae or any algae that’s attached and not free-swimming in the water, so you still need adequate chlorine for that, UV or not. Go SWG and you’ll never look back.
L,
It is Texas!!!... We never let facts get in the way of a good myth..
Thanks,
Jim R.
My next question is about Pentair vs Jandy. I know it's better to use all equipment from one brand so how I decide which brand to go with? Is this a Ford/Chevy discussion? I am in Texas as we've discovered! My PB likes Jandy, but says Pentair is generally a little cheaper. It will be a 12x22 plaster pool with a spa using SWCG as recommended here.
- May 3, 2014
- 62,684
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Pretty much. The issue with Jandy is zero DIY support, and any software upgrades to their equipment you must have a service company install new hardware.
Many of us are more Pentair centric. Best pump on the market (Intelliflo3), Intellicenter is OTA upgrade of software, etc.
Don't you ever etc an IC60 again.
(That's the honking SWG Lweber. I have one. Its awesomesauce).