Choosing a sanitizier for new pool build

[Tul9033]

We are in the final stages before actual construction starts on our 17'x34' free form sports (3.5'/5.5'/5') 13K gallon w/ Paramount infloor, River Rok, heater, w/ DE filter. The PB has spec'd an ozone w/ UV system @ $1500. After spending several hours on this site I'm finding there seems to be very little support for ozone. This has me seconding guessing the PB and considering going with a SWG.
Most of the threads I've read are from 2010-2013. Has there been any change in the technology from then to now that might have changed the consensus from a few years ago against ozone? The PB will do salt if we want, but the concern for them and salt was the negative impact on decking salt has. The impression we got from the PB was Ozone/UV was the latest/greatest and SWG was on it's way out. Even with ozone/uv they spec'd a small chlorinator as part of the build.
Initially I thought ozone w/ UV was two separate processes, now I am seeing that there are 2 technologies ozone through corona discharge and ozone through UV. The technical papers I've read are showing that ozone level generated through UV is much lower than by CD. The thought was we would only be running the pump 4 hours a day, making ozone seem less and less desirable since we aren't getting any benefit from ozone with the pump off.

 

[Donldson]

Welcome to TFP!

Very few PBs are well versed in pool chemistry. Nothing wrong with that, they are there to build the pool not maintain it, but when they start offering advice their shortcomings can be costly for the pool owner.

First, SWG is not on its way out, it seems to be growing as more people realize the benefits of not using pucks to chlorinate. SWGs do not add stabilizer to the pool and when done right give a cost savings over the life of the cell versus typical pool store care. When following TFPC methods the cost is generally equal to manually chlorinating with liquid chlorine and most of us here do one or the other. The only concern with the decking is if you are using a very soft stone. In either case properly sealing the decking is recommended and should mitigate any issues. When properly managed we have seen very little problems with SWG users on the site.

As for ozone and UV, there have been no changes to these in the past few years. UV is still entirely unnecessary in an outdoor pool that gets sunlight. Ozone acts as a secondary oxidizer, but in a residential pool this really is unnecessary as the chlorine provides enough oxidation. Public pools with a very high bather load and bromine spas are about the only place I can think of where ozone makes sense, not in a pool that will only see a few people a day on average.

Since you have been reading around the site I hope that you have found the Pool School link above. By using a proper test kit and following the chemical guidelines there (unless they interfere with any warranty requirements, be sure to look in to that) you will ensure a clear pool and extended life from your salt cell. I am sure you will be quite happy with the results and glad you skipped on the PB suggestions.

 

[robdac]

Ozone? UV? Umm... no thank you. You need chlorine as a sanitizer. People use it for a reason and the reason is that it works. You can get it from bleach or make it yourself with a SWCG. I like my SWCG. If it broke today I'd buy another tomorrow. But manual bleach additions or a stenner pump work fine too.

 

[Isaac-1]

What they said, you don't need it in an outdoor residential pool, both technologies have a place, but unless you are going to have lots of people in your pool all day long every day, it is not needed in an outdoor residential pool. Indoor pool, maybe, therapy pool, maybe, swim spa or hot tub, sure it has a place, but out door residential pool, nope not needed, and don't buy into the hype about it lowering the need for chlorine that is another marketing lie that only applies to out of balance pools where stuff is actively growing.

 

[JoyfulNoise]

Just search under UV in the search box and you'll find lots of current info. Here's something I wrote late last year on UV -

Can I leave pucks in my in-line chlorinator when it's off?

If you want my opinion, I agree with those above - forget about UV and ozone and go for the SWCG...you'll love it!!

(just get a variable speed pump for the pool and oversize the SWG by 2X your pool volume and you'll be super happy)

(oh, and don't let the PB sell you on chemical automation systems, eg, Pentair IntelliChem or Hayward Sense&Dispense. ORP chlorine control is not needed)

 

[Tul9033]

Thanks for the replies. What our PB and from my understanding many pool builders are having problems with is the salt water spalling the pool deck and coping.
We currently have travertine spec'd for our coping and salt concrete for the deck. It is a concern for us. However, we actually like the spalled look of travetine. Spalled concrete, not so much.

 

[JoyfulNoise]

Thanks for the replies. What our PB and from my understanding many pool builders are having problems with is the salt water spalling the pool deck and coping.
We currently have travertine spec'd for our coping and salt concrete for the deck. It is a concern for us. However, we actually like the spalled look of travetine. Spalled concrete, not so much.

View attachment 46206

Concrete should be fine. Mine is going on 4 years old and shows no signs of any damage at all.

Travertine is an issue but you can seal stone. Dry Treat 40sk and DuPont StoneTech are sealants against salt. It will add to the expense of the build but it is an option.

 

[gwegan]

What is interesting is there are not many threads on here regarding salt destroying stone. Even in OK and Texas. Either they don't complain on here or the risk is not as high as pool builders state.

 

[Donldson]

I do want to make sure you are aware of a couple things too. First, all pool water has salt. Pucks, liquid chlorine, powdered chlorine, muriatic acid, they all add salt. Most non-SWG pools end up over 1000 ppm of salt after a couple of seasons. So sealing stone is not a bad idea for any pool, but if they are not seeing problems with normal pools after a decade plus of use then the problem might be a bit overblown.

Second, and most important, your choice is not between salt and UV/Ozone. If you decide to forego salt you still don't need, nor will see much benefit from a UV or Ozone system. You can choose to chlorinate manually with liquid chlorine, or have a liquid chlorine automation system like a stenner pump installed. You can use a puck feeder if you want, though we are not too keen on those given the problems that come from regular puck use. So even if you are not keen on using salt for whatever reason there is still no reason to spend your money on a UV or Ozone system.

 

[pooldv]

I'll be another advocate for saltwater, love it. We are in TX and we have OK flagstone coping and concrete deck. We are ramping up our 5th pool season right now. All of our stuff looks pretty much the same as the day it was installed. Either the idea that salt destroys flagstone is a myth or I got some great flagstone. It is unsealed and we have been in drought most of the years we've had a pool so rain isn't washing the salt off. And we swim almost every day. We even spent one year with way too much salt in the pool, over 4500 ppm (normal is 3400 ppm), because I wasn't aware of the SWG giving false low salt warnings when the water is cold.

 

[Tul9033]

A relative has salt in the DFW area with OK flagstone and they are experiencing flaking of their flagstone. They are using a Nature2 Soft. They are finding pieces of the flagstone in the pool as well.
Spoke with our PB today and we can go with the Jandy Tru Clear salt chlorinator (they use all Jandy equipment) for $950 (includes salt) vs $1500 for the ozone/UV.
Probably the main reason driving us to salt over just straight chlorine is the water feel. I think the water feels super soft and less harsh all over.

 

[pooldv]

Yes, saltwater does feel nice. I have some pieces of flagstone that have some flaking. A few of them are in the pool coping and the worst ones are on some flagstone paths nowhere near the pool. I think they were going to flake no matter what. I have a lot more flagstone that isn't flaking.

I am OK with blaming their flaking flagstone on the Nature2 minerals.