Iron stain from pool salt - all or most salts have iron.

[tcat]

I'm thinking my cell gets build up because my CH is around 450. I think I'll try borates to help get my pH down. I add 4 oz MA daily to keep it at 7.5-7.6.

 

[Bperry]

Hopefully no one here is chlorinating with pucks.

I did all this past year with new plaster to add CYA and supplement the SWCG. Didn’t have to add a drop of acid all summer as it kept the pH pretty stable.

 

[mknauss]

A CH of 450 is easily managed. Again, keep the TA as low as you can and keep pH stable.
Borates will definitely help. Adding them should essentially eliminate scale buildup with managed TA and pH.

 

[nuttyp]

Hopefully no one here is chlorinating with pucks.

Indeed! Not me that's for sure

 

[Saturn94]

except for the fact that we have no idea what the ”stain inhibitor” chemical is, no ingredients listed. A bit of sequestrant perhaps? Most TFP folks don’t like adding unknown chemicals.

This also applies to the Aqua Salt product. It also advertises stain inhibitors without disclosing what chemical is used (I tried calling them, but the person I spoke to had no clue). The time I tried it, it was very dirty; lots of nasty grey scum floated to the surface.

 

[ajw22]

This also applies to the Aqua Salt product. It also advertises stain inhibitors without disclosing what chemical is used (I tried calling them, but the person I spoke to had no clue). The time I tried it, it was very dirty; lots of nasty grey scum floated to the surface.

I have been using Aquasalt for the last few years with no problems. I use about 15 bags a year.

I buy it at my local Pool Store for $12-$14/bag. They go through a lot of it for their service customers. If it caused problems, I doubt they would be using it.

 

[tcat]

I have been using Aquasalt for the last few years with no problems. I use about 15 bags a year.

I buy it at my local Pool Store for $12-$14/bag. They go through a lot of it for their service customers. If it caused problems, I doubt they would be using it.

15 bags a year! I'm in Texas and use 1 bag a year. You must get a LOT of rain!

 

[sande005]

@Bperry noted it. For the CH build up - turn on the CSI tracking in PoolMath, and strive to keep it always negative. Yes, too negative can be bad for plaster/tile etc. For those, keep it higher than -.3, but still slightly negative. Don't go positive. That will reduce or maybe even eliminate the buildup. Note that the value is interactive with almost all the other parameters - so changing one will necessitate a change in one or more others. Temperature and pH make bigger swings.

 

[ajw22]

15 bags a year! I'm in Texas and use 1 bag a year. You must get a LOT of rain!

The pool water level is drained down and closed for the winter. When opening the pool and adding water, salt is usually around 2300 ppm. I use about 10 bags when opening the pool in the spring.

I can get a few big storms during the year that require draining down the pool to prevent it from overflowing. I hate dumping the chemicals but can't help it. So the other bags replace the dumped chemicals.

 

[pjt]

Diamond Crystal Water Softener pellets:

You tested the "Bright & Soft". It would be interesting to see the result from the Solar Naturals, which is very popular for saltwater pools.

I still may have misunderstood and I would love to leave the TA lower.

I try to get it near that 70, 80 or even 90, that's when my PH keeps trying to rise correspondingly faster, and I have to add muriatic acid to keep PH down, then my TA falls again. I've been in that cycle for years.

I'll let the TA drop to 50 and keep an eye on PH, now realizing the goal is simply to have enough TA to keep PH from crashing lower which of course is bad for many reasons.

TA of 50 or above is good. The lower the TA, the slower the pH rise. With a TA of 50-60, the pH will likely stabilize in the high 7s, which is perfectly fine.

Under normal circumstances, a non-trichlor pool should never need baking soda. You're chasing your tail with baking soda --> MA --> Baking soda --> MA, etc..

 

[AUSpool]

I use a brand of salt called Mermaid which is produced by Cheetham. They produce salt by crystallizing sea water that is extracted from the great southern ocean. The crystallization process can be used to exclude undesirable elements that are normally found in the sea water, but there are limits. They are pretty open about the quality, 99.4% pure NaCl with a maximum iron content of 10mg/kg. To put that into perspective a 20kg bag of salt will raise the salt in an average 30kL pool by around 700ppm and the iron by 0.03ppm. As the salt is lost to overflowing rain, splashout or backwashing so to is the iron content so it would be expected to remain constant as more salt is added to maintain an ideal level.

 

[Saturn94]

I have been using Aquasalt for the last few years with no problems. I use about 15 bags a year.

I buy it at my local Pool Store for $12-$14/bag. They go through a lot of it for their service customers. If it caused problems, I doubt they would be using it.

That’s good to know.

The grey scum I experienced (had to clean it off the waterline) really turned me off to it, not the mention the mystery ingredient. Perhaps my experience was a fluke.

Has anyone confirmed that using this salt really does prevent iron stains? I’ve been using Jacks Magic Purple Stuff occasionally to ward off iron staining. It works well, but it’s getting pretty pricey. Oh, and apparently using enough Jacks magic can cause interferences with the Taylor salt test (false high readings). I found this out the hard way.

 

[tcat]

I've always used Diamond Solar Naturals from HD with no issues. Was $6 now $8.

 

[Saturn94]

I've always used Diamond Solar Naturals from HD with no issues. Was $6 now $8.

That’s what I’ve been using for several years now. Gradually, given enough time (weeks?), iron stains will start showing, especially on the steps. But to be fair, it seems no matter what I’ve used over the past 21 years, iron stains slowly show up given enough time.

 

[tcat]

That’s what I’ve been using for several years now. Gradually, given enough time (weeks?), iron stains will start showing, especially on the steps. But to be fair, it seems no matter what I’ve used over the past 21 years, iron stains slowly show up given enough time.

Good thing I have Pebble finish that never looks bad. I also only need 1 bag per year, so gets dissolved quickly.

 

[Bperry]

That’s what I’ve been using for several years now. Gradually, given enough time (weeks?), iron stains will start showing, especially on the steps. But to be fair, it seems no matter what I’ve used over the past 21 years, iron stains slowly show up given enough time.

Are you sure it’s the salt?

 

[ajw22]

Has anyone confirmed that using this salt really does prevent iron stains?

It is hard to prove a negative.

I never had iron stains before using Aquasalt and haven't had it since using it.

 

[nuttyp]

You tested the "Bright & Soft". It would be interesting to see the result from the Solar Naturals, which is very popular for saltwater pools.

Thanks, I see it's available for $7.50 at my local Tractor Supply Co. I'll pick one up and test it. Is this the one you mean @pjt , which states "for water softeners"? Not that water softener statement matters much I guess.

I use a brand of salt called Mermaid which is produced by Cheetham

I don't see mermaid around here in the Southern USA, will keep an eye out, thanks. Does seem popular in Australia!

This also applies to the Aqua Salt product. It also advertises stain inhibitors without disclosing what chemical is used (I tried calling them, but the person I spoke to had no clue). The time I tried it, it was very dirty; lots of nasty grey scum floated to the surface.

My bags of aquasalt did not have the mention of the new and improved mighty stain inhibitors, but point well taken. I suppose I get a tiny bit of bubbly scum, gray or otherwise, from almost every salt I've tried. I just figured it's part of the game, but since I now have six different types of salt in storage, I'll pay more attention next summer, maybe add "scum production" to the measurements

 

[nuttyp]

You're chasing your tail with baking soda --> MA --> Baking soda --> MA, etc..

I guess one can't overstate the implications of that tail chasing!! Aside from my own brand of "thickheadedness" on the matter, I still wonder how many folks are doing similar. Especially given the numbers among us cleaning CA off cells, and the numbers among us injecting or otherwise adding muriatic acid regularly. And the number of places - in poolmath, ABC's and related posts - that leave at least some of us thinking more TA is better ('70, 80, 90 or higher TA'). I may start a new post about it in chemistry area, in case I'm not alone in my former ignorance

I noted earlier that I don't use trichlor pucks, but I do keep a sealed bucket of them in a plastic outdoor bin in case of emergency, like if power is out for an extended period and liquid chlorine becomes unavailable. Both those events happen when stores are closed post-hurricane. Maybe I could engage my wife to "stir the pool" as the pucks dissolve - (just kidding!). I had also planned to use the pucks to add CYA (turning off SWG) but it turns out the puck prices have skyrocketed and we can get CYA/stabilizer for under $3 per pound - eg Puritech here.

 

[Bperry]

And the number of places - in poolmath, ABC's and related posts - that leave at least some of us thinking more TA is better ('70, 80, 90 or higher TA').

Make sure to let people know where that idea came from. Pool math gives recommendation of 50-90 so it’s not clear where the confusion is.