chlorine generator

[spike]

i'm considering purchasing a salt/chlorine generator. i've heard only the positives. what are the minuses? any particular brand?

[Backglass]

WATCH THIS and READ THIS before deciding...there is a bit of controversy stirring and two different camps.

[Flapoolguy]

Have had my pool a year now with salt system and so far no problems at all, my deck is cement not stone as that might make a differnce. as stone is suposed to be hurt more from salt as i have heard anyways.

The only thing is do not get metal chairs and tables as they will leave rust spots on the deck from the saltwater .

[Backglass]

Have had my pool a year now with salt system and so far no problems at all, my deck is cement not stone as that might make a differnce. as stone is suposed to be hurt more from salt as i have heard anyways.

The only thing is do not get metal chairs and tables as they will leave rust spots on the deck from the saltwater .

Make sure you seal your concrete. Its the porous rock that has the problem and unsealed concrete is VERY porous.

[Guest]

Its is painted with deck pool paint so it should be ok, pool builder had it all done but as for all work done by someone else, Paint job is not as good as it could be so will be repainting in soon as weather gets dry here in florida. to do it in the summer would not be a good idea as it could rain at any time
Thanks for the heads up on the cement.

[chem geek]

It's really premature to conclude that any specific material will be a problem with the extra salt in an SWG pool. We just know that it's a problem for some materials in some areas. If you live in a part of the country where summer rains are common, for example, then your hardscape and coping surfaces will get rinsed regularly so probably won't have any problems. It's areas with less or no rain that are of more concern, but even then the problems aren't consistent so other factors are present.

I agree, however, that sealing concrete will ensure you protect it. Our textured concrete is sealed every year with "Glaze ‘N Seal Multi-Purpose Clear Sealer" as recommended by the installer.

It seems that plain (not stamped or textured) concrete is not as much at risk as soft stones such as limestone. But again, this is very dependent on the specific stone and even the specific vein or quarry where it was mined. Also keep in mind that a poor quality stone will degrade in a low-salt environment as well.

Richard

[whoville]

My opinion? Run away from it as fast as you can! They are a pain to maintain and once you get scale in the cell you might as well throw it away. I've had mine for 3 yrs and it has been nothing but work. I'm going to take mine out and drain the pool to get rid of the salt and go with a regular chlorinator. Just my two cents worth.

[chem geek]

The problem is that "a regular chlorinator" uses Trichlor pucks/tabs so will build up Cyanuric Acid (CYA) over time rendering the chlorine less effective. In order to prevent algae, you'll need to use a supplemental algaecide at extra cost and the Trichlor is very acidic so you'll need to adjust pH regularly as well. If you have a smaller pool and frequently backwash or otherwise dilute the water, then you can keep the CYA level from rising as quickly. There is no free lunch here.

If one uses chlorinating liquid or 6% unscented bleach as their primary source of chlorine, then they will not increase CYA (you still want CYA in the water, but at a fixed level). The downside is that you need to add the chlorine every day or two unless you have a pool cover opaque to the UV in sunlight and even then need to add the chlorine about twice a week (that's my situation). To automatically dose liquid types of chlorine, you need a peristaltic pump or The Liquidator or similar system and it has it's own scaling ("white stuff") problems.

For me, I use 12.5% chlorinating liquid I buy at my local pool store where they reuse the bottles (better than recycling) and I add chlorine twice a week to my pool. I have a 16,000 gallon pool and the chlorine costs about $15 a month. I only add a couple of cups of acid every month or so. I have an electric opaque safety cover so my chlorine usage is relatively low at around 1 ppm FC per day, even though the pool is used almost every day for 1-2 hours.

Richard

[lonestar]

If you own a salt system you must adjust the PH every week. And every 3 months you must get your CYA checked at a pool store and check your cell.

This is much less work then the chemical guessing game required on a regular pool.

With that said, lets get to coping. I am from Austin, Texas. Many pool companies that installed salt systems a few years ago went back and took them all out. Many plaster companies here and in Houston will not warranty the plaster if you have a salt system installed.

In Austin its common to use limestone coping. The stone is very soft and is nice to walk and sit on. Salt water eats limestone. Planet Earth on Discovery stated that all caves in the world are limestone thats been eaten away by saltwater. Sealing the limestone can help. Ultimately, I would not install a SWG on any sort of flagstone, sandstone, limestone etc.

Any stone you might describe as soft I have seen on a pool being eaten by a SWG. I care for a pool which has a waterfall made of soft stone and a SWG. The water has made a pathway behind the waterfall and much of it just wastes into the ground. This is a 15' tall waterfall and were talking about hundreds of gallons of water a week!

Dont get me wrong though. I love Salt water pools. If i bought a pool I would get a white plaster pool with concrete coping and a SWG. The waters high salt content means it doesnt steal your salt, making it feel better on your skin.

There does need to be more testing done on salt water's effect on plaster as the Arch Chemical study raised a few questions in this area. Hm, looking for that article online I did not find it. They had a salt water test pool built which showed considerable plaster degradation. This was only one pool out of 30 or so and was the only salt pool. It was not considered part of the plaster test but was built just to see if anything interesting happened, so its results only raise questions...

[chem geek]

One can manage the pH rise normally associated with SWG pools by having the Total Alkalinity (TA) lower and using 50 ppm Borates in the pool (see this link). The pH target can be higher (about 7.7) and the Calcium Hardness (CH) a bit higher to ensure the saturation index is near or just below zero. This can be calculated with The Pool Calculator.

The saturation index is more negative by about 0.2 in an SWG pool with 3000 ppm salt (3200 ppm TDS) compared to a non-SWG pool with 350 ppm salt (525 ppm TDS). So one must compensate for this to not have plaster slowly dissolve. This is easy to do by adjusting the target pH and CH level as noted above.

You don't have to go to a pool store to get the CYA level checked and in fact many pool stores give inaccurate results for their tests, especially for the CYA test. You can test for everything accurately yourself by using either the Taylor K-2006 test kit you can get at a good online price here or the TF100 test kit from tftestkits(dot)com with the latter kit having 36% more volume of reagents so a little less expensive "per test".

The Arch Chemical plaster study shown here was about high CYA levels. I can't find one showing salt's effects on plaster. Even this CYA level study wasn't able to be reproduced by Que Hale at PoolChlor and it's not clear if the carbonate alkalinity was maintained consistently in the study (i.e. the TA raised as the CYA was raised).

Richard

[lonestar]

I cannot find the Arch Chemical study link I originally found a few years ago that talked about this. I believe it was printed in a publication like pool and spa news. When the Arch study was done, they built a bunch of test pools and just for fun built a salt pool and there was some other sort of experimental pool built.

These last two pools didnt have any control group and were not considered part of the experiment for scientific data. The article only mentioned, therefore, that the salt pool had the worst plaster degradation. It could be any number of factors that they overlooked because salt water pools was not the focus of the experiment.

I mention it only in passing, but some chlorine generator manufacturer should certainly test it. Of course it took years to get someone to test CYA so I doubt we'll be seeing it soon.