Lithium Hypochlorite For Routine Care

[bhbranum]

For the sake of this question, lets pretend Lithium and Sodium Hypochlorite cost the same. I have been using bleach for routine care of the pool for a while now. Maybe because of the south Texas heat and little rain we get, my pool gets very salty (and of course TDS always measures high as well). You can taste it and I am worried that my stone coping is being affected because of the grit on the bottom of the pool. I might be willing to switch to Lithium despite the cost to at least see if it makes a difference. The problem is the "other ingredients" that make up 2/3 of most lithium shock. I heard somewhere that salt is a high percentage of these "other ingredients" but I can't find a definite answer anywhere. Does anyone know what these ingredients are for the more common brands? Also, Cal-Hypo is not an option because of the hard city water and I don't want anything with CYA either.

Also, I can split this off if I am not supposed to ask 2 questions at once but it is related. I see some people saying the Lithium has a high PH and some say it is neutral. It would be nice to know for sure because liquid chlorine also causes a high acid demand for me (at least relative to tablets with CYA which I used to use).

 

[JoyfulNoise]

The answers to your questions are here - Cost Comparison of Chlorine Sources

Lithium hypochlorite will increase saltiness of the water as much as any other other source of chlorine and it is definitely going to raise pH slightly similar to bleach because it will add "extra" hydroxide. The only solid forms of chlorine that do not contain "excess salt" are the cyanurates (dichlor and trichlor). All forms of chlorine will eventually add to the chloride level of the pool because the reduction of chlorine during oxidation and sanitation reactions produces chloride ion (Cl-).

Lithium hypo is expensive and it adds a few other chemicals to the pool water that are not great (chlorates and sulfates). So the take away from this is to just stick with bleach.

By the way, have you ever measured your salinity with a salt test kit? Long term use of any chlorinated sanitizers in a pool with little fresh water exchange and lots of evaporation will build up chloride levels over time. It is not at all unexpected to find chlorinated swimming pools that will have chloride levels up near 1500-2000ppm with just a few years of chlorine use.

 

[bhbranum]

Thanks for the info. I think deep down I expected that. There just isn't any disinfectant that won't build up some undesirable affect over time. No, I haven't ever tested for salinity since I can taste it (and the kids are not shy about letting me know when they think it is too salty as well). I try to limit my water replacement to winter time but this is too early in the summer to already be getting this so I might have to do a partial replacement.

 

[JoyfulNoise]

Install an SWG. You'll add ~3500ppm salt to the pool and then nothing else. I rarely, if ever, have to add chlorinating liquid to my pool. Just muriatic acid to control pH which isn't really a big deal.

 

[bhbranum]

When we built the pool, all contractors either refused to do salt water or made you sign a waver on the warranty. From what I understand, the hard water we have in San Antonio combined with salt is bad for the stone coping. It wasn't just one contractor so I believe it. I, also, see evidence of it because of the relatively low salt levels I have and the amount of stone grit at the bottom of my pool. SWG was my first choice because my buddy a few hours north of me loves his.

 

[JoyfulNoise]

When we built the pool, all contractors either refused to do salt water or made you sign a waver on the warranty. From what I understand, the hard water we have in San Antonio combined with salt is bad for the stone coping. It wasn't just one contractor so I believe it. I, also, see evidence of it because of the relatively low salt levels I have and the amount of stone grit at the bottom of my pool. SWG was my first choice because my buddy a few hours north of me loves his.

That's B/S on the part of the PBs. See this thread -

Texas vs. SWG - What is the deal

There's a post in there by a Texas service manager for a pool company where he admits it has nothing to do with salt but poor water chemistry management on the part of misinformed pool owners assuming SWGs mean they never have to worry about water chemistry and pool service companies that don't understand the fundamentals of how SWGs work. Because of the abuse pools received from all of the misinformation, subcontractors refused to warranty their work if PBs sold SWG systems. Since PBs did not want to be left holding the warranty bag, they bad mouthed SWGs and went more towards "alternative" sanitizer systems.

Are there soft stone materials that can be damaged by salt? Sure. Can the effects be easily mitigated with better choice of materials and construction practices? Absolutely.

Salt is not to blame and there is no magical interaction between salt and local water hardness, that's just a lazy excuse used by PBs that don't want to do a better job that what they know how to do.

And, logically speaking, if salt was a problem in your pool, you'd already be seeing it because if you can taste salinity, then your salt concentration in the pool is probably very close to 2000 to 3000ppm salt. That's the limit of human salt taste AND fairly close to the operational point of an SWG (~3600ppm).

 

[cfherrman]

The gulf has a ppm of 32,000 and 36,000

 

[bhbranum]

That's B/S on the part of the PBs. See this thread -

Texas vs. SWG - What is the deal

There's a post in there by a Texas service manager for a pool company where he admits it has nothing to do with salt but poor water chemistry management on the part of misinformed pool owners assuming SWGs mean they never have to worry about water chemistry and pool service companies that don't understand the fundamentals of how SWGs work. Because of the abuse pools received from all of the misinformation, subcontractors refused to warranty their work if PBs sold SWG systems. Since PBs did not want to be left holding the warranty bag, they bad mouthed SWGs and went more towards "alternative" sanitizer systems.

Are there soft stone materials that can be damaged by salt? Sure. Can the effects be easily mitigated with better choice of materials and construction practices? Absolutely.

Salt is not to blame and there is no magical interaction between salt and local water hardness, that's just a lazy excuse used by PBs that don't want to do a better job that what they know how to do.

And, logically speaking, if salt was a problem in your pool, you'd already be seeing it because if you can taste salinity, then your salt concentration in the pool is probably very close to 2000 to 3000ppm salt. That's the limit of human salt taste AND fairly close to the operational point of an SWG (~3600ppm).

I can believe that, but at this point I don't feel like spending the money (and also possibly voiding any warranty that is left). It sounds like I, essentially, have a salt pool anyway. My buddy likes his because it is low maintenance but dumping chlorine in every couple of days isn't that hard. We compared maintenance cost and it seems similar. The person that sold him his pool downplayed the replacement of the cell that is required every so often and we calculated that you, probably, wouldn't choose one over the other based on maintenance cost alone. EDIT: Also, the sales guy told me my pool was maintenance free because of the auto-puck feeder that uses an ORP sensor to only feed when necessary and the auto-acid feeder that uses a PH sensor. The auto-acid feeder is awesome but I no longer use the puck feeder except on vacation. Bottom line...there is no such thing as maintenance free as anyone on this forum is well aware of already.

 

[JoyfulNoise]

I can believe that, but at this point I don't feel like spending the money (and also possibly voiding any warranty that is left). It sounds like I, essentially, have a salt pool anyway. My buddy likes his because it is low maintenance but dumping chlorine in every couple of days isn't that hard. We compared maintenance cost and it seems similar. The person that sold him his pool downplayed the replacement of the cell that is required every so often and we calculated that you, probably, wouldn't choose one over the other based on maintenance cost alone.

This article was written about 2 years ago so the costs may be slightly different, but the conclusions are pretty universal -

Economics of Saltwater Chlorine Generators

If you purchase and install an SWG and if it is properly maintained so that you get the full manufacturers rated lifetime out of it, then the cost of the SWG (including all additional chemical maintenance) is equivalent to using liquid chlorination over the same time period. In effect, you are simply buying all of your chlorine up front when you use an SWG. The return on investment (cost of FC over time) gets better with each replacement as the replacement cells are generally cheaper than a new installation. SWG maintenance is not hard at all and, if one purchases from a well known brand (Hayward and Pentair are the top of the line with good warranties and customer support), they can last for a very long time assuming water chemistry balance is maintained. Unfortunately, many pool owners don't take the time to learn how to care for their pools themselves and/or leave it up to pool service companies under the assumption that they are "the experts". That, unfortunately, is where the problems start....

I understand your situation with the warranty and you certainly have to abide by those conditions if you expect the PB to honor his end of it. Unfortunately, the warranty is predicated on misinformation and the typical pool owner rarely has enough information prior to their builds to refute what they consider the "expert's advice". I certainly could have used more plumbing/hydraulics knowledge to avoid some obvious inefficiencies in my setup but luckily had a pool builder that preferred to build salt-water pools.