Low TDS (Freshwater) Chlorine Generators

[rlab]

Hi, first time poster from Australia, just starting to plan and research my first ever pool.

A recent fad here is companies releasing Low TDS Chlorine Generators (Some call them freshwater chlorine generators). These are standard SWG's, but with an oversized cell so they can run on very low TDS levels, as low as 900ppm.

The idea of an SWG system that is basically freshwater is pretty appealing, but I am always wary of this kind of new tech. What do people think? Is there any benefit in running such low salt levels? (chlorine levels would still be the same as a standard SWG).

 

[Newdude]

If you did not like the feel of a salt pool, then this would be the way to go. Providing it works as promised of course.

 

[Jimrahbe]

R,

All marketing speak so far... The key is how much chlorine do they produce per hour when the salt is 900 ppm??? Without that info any comparison is useless..

I also suspect that you have to use their "special" salt at some ridicules price..

Thanks,

Jim R.

 

[ajw22]

Sounds similar to the AquaRite_Low_Salt_Chlorine_Generator

No new tech there. Just a large cell being run at suboptimal salt levels.

 

[rlab]

Ok yes same as the AquaRite low salt model. The low salt chlorinators all have a rated chlorine output, same as any other SWG. They are just bigger (and more expensive) to get the same chlorine out as a standard SWG.

I just assumed less salt is always better (assuming chlorine output is at required level). Less cost to maintain, nicer feeling/taste to swim in, less potential for corrosion? Is that not the case?

 

[mknauss]

There is no issues maintaining a SWCG pool with salt at 3000 ppm or so. Feels great to us, I can't taste it, no corrosion.

I would see no reason to use a low salinity SWCG and the issues that come with it, primarily cost.

 

[Donldson]

Less cost to maintain, nicer feeling/taste to swim in, less potential for corrosion? Is that not the case?

Odd, some people add salt to their non-salt pools because they believe it improves the feeling of the water. I haven't heard of anyone trying to keep their salt level low to improve feel. As for cost and potential for corrosion, doubtful either of these would be true. Salt contributes a lot less to the corrosiveness of water than people think, at any rate the difference between 1800 and 3000 ppm would be negligible. I also can't imagine how the cost would be any different. Salt is cheap and electricity would be roughly the same, though perhaps even more.

Not that I think there's anything wrong with the equipment, I just don't see much point.

 

[Jimrahbe]

R,

More marketing speak... In my opinion, saltwater pools feel better to swim in then non-saltwater pools... What corrosion? I have three saltwater pools and none of them have any corrosion.. If the cell costs more, I can't see that a few bags of salt a year is going to make much difference in total costs.

I still see no number for how much CL they produce... The less they produce the more you will have to run your pump.

Before I could make any kind of decision between a regular SWCG and a "freshwater" SWCG, I'd want facts.. I'd want to compare the cost of each cell, the amount of CL the cell can make per hour, the expected lifetime of each cell in run hours. What salt level is required to meet the expected CL production. Is any special salt required?

Thanks,

Jim R.

 

[ajw22]

I just assumed less salt is always better (assuming chlorine output is at required level).

Pool water often has a salt level of 1,000 ppm or higher from the accumulation of salt in liquid chlorine. Most folsk who don;t have a SWG don't know how much salt they have since they don't measure it.

Less cost to maintain,

Check the cost of replacement cells. If it is a big cell it will be expensive.

nicer feeling/taste to swim in,

People add salt to their pool water because they like the silky feeling.

less potential for corrosion?

As stated above, most pool water already has salt. There is not a material corrosive differnce between 1,000 ppm and 3,000 ppm of salt.

Is that not the case?

I think the jury is out.

 

[rlab]

Regarding the chlorine output level, in Australia it is mandatory for all SWG to be sold with a rated chlorine output level in g/hour. So I can look at the specs and see they perform equivalently to a standard SWG. An example from 1 manufacturer:
- WaterMaid EcoBlend RP9 (Normal model) - chlorine 30g/hour @ 3,000ppm
- WaterMaid EcoBlend RP13 (Low Salt model) - chlorine 30g/hour @ 1,000ppm

So the low salt model is rated at the same chlorine output, just at much lower TDS level. The difference is the Low Salt model costs twice(!!!) as much as the normal model, the replacement cells are also similarly expensive.

I don't mind a higher price if it is going to give better "quality" water. But it sounds like people think that is not the case.

 

[JoyfulNoise]

The only time TDS is important is when you're talking about drinking water or water used for agricultural irrigation. For swimming pools, TDS is meaningless. Corrosion has more to do with pH and dissolved oxygen levels than chloride. You really are gaining NOTHING substantial by going with a "low salt" model other than the psychological boost anyone feels when they're using "the latest gadget" ....