View Full Version : My First post - high salt?
jonnymac
08-20-2011, 01:23 PM
Hello Everyone,
My pool: 15,500 gal, Colored Plaster, Attached Spa, Flagstone (although it's more like Sandstone - more on that maybe in a later post) Coping, Sand Filter (currently filled with Zeolite), Propane Heater (with an alloy heat exchanger to prevent corrosion - but metal still flakes from the HX - more on that maybe in a later post), SWCG, In-Floor Circulation Popups.
My chemicals (I'm a fan of BBB): Muriatic Acid - several times per week to lower pH (although I'm seriously contemplating the higher pH concept because I'm tired of fighting it so hard). Baking Soda - several times per week to raise the TA back up after the acid lowers it. Borax (as I understand it) for pH stabilization. Jack's Magic Purple following each refill/top off to sequester metals.
My fill water: Well water. But it goes through a sediment filter, carbon filter, softener, and finally a hose-end "PreFresh" brand fill filter before it reaches the pool.
My season: Year round. Covered roof, aluminum/screen enclosure. Plastic windows during the cold season.
My chemistry: I maintain all parameters in the standard bands (but like I said, I'm probably going to give the higher pH thing a try), with the exception of TDS. The TDS got away from me recently (5600 ppm) when I topped off without using the PreFresh fill filter, yes even with the other filtration and softening. Note: Salt was also high (manufacturer's band 2700 - 3400 ppm) at 3800 ppm - confirmed with digital Salt meter. So...
I'm currently in the process of partial drains and refills to lower TDS and Salt. It works great. TDS is 4600 ppm and Salt (was) 3300 ppm. Problem is...
After the last Baking Soda addition, Salt rose back up to 3500 ppm and TDS remained at 4600 ppm. Question...
Is it possible the Baking Soda (and/or the acid for that matter) caused the Salt to rise?
Thanks in advance,
jonnymac
aylad
08-20-2011, 01:34 PM
Hello, and welcome to the forum!!
Baking soda and acid don't cause the salt to rise. I don't know why you're getting an increased salt reading--one of the SWCG folks should be by here shortly and can probably answer that one for you.
I just wanted to understand something...you say you are using acid to lower pH, then baking soda to raise alk, then using Borax, which raises pH--why don't you just use the acid to lower the pH to 7.6, and leave the alk alone, since the lower alk is better for stabilizing the pH in a SWCG pool? Otherwise, you are battling yourself with chemicals!!
jonnymac
08-20-2011, 02:10 PM
Hi aylad,
Leaving the alk alone sounds good to me. Should I still maintain some kind of limit or just let it go where ever?
As for the borax, I don't use it to raise pH. I'm under the impression it helps maintain pH (minimizes pH bounce) once the pH is where you want it. So I only add it occasionally to maintain about 50 ppm borates. I'll get a current borate concentration next time I test it.
jonnymac
PoolDoc
08-21-2011, 06:28 PM
Hi Jonny;
Janet (aylad) is right that baking soda doesn't increase your salt (chloride) levels, but . . .
The problem is, you may not be measuring salt! If you are going by the 'salt meter' built into your SWCG, or if you have a salt meter, those don't actually measure salt, they measure conductivity. And baking soda DOES increase your conductivity, as does any chemical which ionizes when it dissolves.
If you have 'difficult' fill water -- and it sounds like you do -- you may be adding water that's low in actual salt (chloride) but high in measured 'salt' (conductivity). I have no experience or knowledge about operating an SWCG under those conditions, so I can't really tell you what to do. I can guess, bu there may be others who know more.
rpoldervaart
08-22-2011, 10:41 AM
Hi Jonnymac,
Are you saying that you already have 50ppm borax and are still battling quickly rising pH? Like you, I have to add acid all the time but was hoping that borax would stabilize it. I hear what you're saying about flagstone being sandstone. My rock is turning to dust. Moss rock on my waterfall is even worse...
Robert
kelemvor
08-22-2011, 12:44 PM
You need to get some sodium chloride test strips, they're a good bit more reliable than the conductivity test that your SWCG does. http://www.amazon.com/AquaChek-Salt-Swimming-Pool-Strips/dp/B002OLP1L6 These are the ones I use (except I bought mine from leslies for a few bucks more).
This way you can eliminate the concern of other substances poisoning your salt conductivity test results.
Don't count on salt readings from your pool store either, as it's likely they're using a conductivity based test. This is the only test that my pool store consistently gives me bad results on (I have them run a test whenever I go buy something, then compare everything to my own results).
aylad
08-22-2011, 06:06 PM
As for the borax, I don't use it to raise pH. I'm under the impression it helps maintain pH (minimizes pH bounce) once the pH is where you want it. So I only add it occasionally to maintain about 50 ppm borates.
Once you get your borate level to 50 ppm, there have been some that report stabilization of pH (as well as lower chlorine consumption, in some cases) but keep in mind that the rest of us use Borax to raise pH, so when you're adding it to maintain your borates, you're going to have to compensate with a little acid to keep your pH from rising (which should also help keep your TA lower, as well).
Janet
jonnymac
08-22-2011, 10:42 PM
PoolDoc, kelemvor, aylad,
Thanks for the good advice. I'll use the salt test strips for more accuracy.
rpoldervaart,
Yes, I try to keep borates about 50 ppm. It's relatively easy. Concentration almost never rises and the only occasions in which I add borax is during partial water replacements. And yes, it minimizes my pH bounce, but like aylad said, it also raises pH. I don't use it to raise pH simply because my pH never goes down. My pH bounce (only in the up direction in my case and not at a rate I would consider "quickly rising") due to the chemical action of my SWCG and due to my fill water being on the alkaline side, would be worse without borates. So, don't be afraid of a little borax. Approximately 50 ppm, as far as I know, shouldn't harm anything.
As for the dust rocks, well that's a different story. If you're interested, I will share what I've done in the past, results, etc.
Thanks again everyone,
jonnymac
famousdavis
08-23-2011, 10:45 PM
How are you measuring your salt levels?
On my SWCG, I get different readings all the time. But over time, I take the lowest reading that pops up with consistency to be my "true" reading. Also, when I've taken water samples to the pool stores (samples taken at the same time and place from my pool), the pool stores give different readings for my salt level. So, I take their salt meter readings with... wait for it ... a grain of salt!
rpoldervaart
08-24-2011, 09:02 AM
As for the dust rocks, well that's a different story. If you're interested, I will share what I've done in the past, results, etc.
Good to hear about the borates. I'll be adding that soon.
I'd be interested in your rocks story. If you post another thread, leave a link here in this thread so I'll see it.
Robert
jonnymac
08-24-2011, 11:19 AM
How are you measuring your salt levels?
On my SWCG, I get different readings all the time. But over time, I take the lowest reading that pops up with consistency to be my "true" reading. Also, when I've taken water samples to the pool stores (samples taken at the same time and place from my pool), the pool stores give different readings for my salt level. So, I take their salt meter readings with... wait for it ... a grain of salt!
Grain of salt, pretty funny. I don't have inconsistent reading issues between the SWCG display, digital dip meter, and the pool store. Like PoolDoc said, these are all actually measuring salinity (and I knew as much, I was just sticking my head in the sand, trying to minimize any more testing/readings than I already do). The pool store reading will depend on the method of measurement.
I've used the Aquachek salt test strips in the past and they're the most accurate I currently know of. So as soon as I receive the bottle I ordered online, that's how I will measure salt from now on, or until something better with reasonable effort and cost comes along.
jonnymac
08-24-2011, 12:19 PM
Good to hear about the borates. I'll be adding that soon.
I'd be interested in your rocks story. If you post another thread, leave a link here in this thread so I'll see it.
Robert
I have the same stone on outdoor walkways and some on columns. Except for the walkways turning darker over time, they're in the same condition they were at installation 5 or 6 years ago. So I'm pretty sure the pool water has caused the degradation of the stone coping. And by the way, my pool's original sanitation was chlorine tablets before I installed a SWCG. The stone degradation started long before the pool was converted to salt.
First of all, I tried all the recommended stone sealers (some even marketed specifically for pool stone) on the shelf and none of them worked for more than a few days/weeks until the stone started flaking again. About five years ago I found a product online called DryTreat. It was made by an Australian company who held the patent and was very expensive ($150 to $200/gallon) depending on the merchant and which product. For that kind of money, I didn't want to screw it up, so I found a local stone care guy who was familiar/certified on the product. I may have located him on DryTreat's website, I don't remember. He did a really good, honest job, requiring several visits, but could not offer the lifetime guarantee because the stone had been previously treated with other products. At this point, I was desperate, and just wanted the flaking/sand/dust to go away.
It worked great for about 4 or 5 years, only about 1% to 5% flaking of what it was before treatment . Over the past year, the stone has begun to degrade again. The stone guy told me the best method to apply the products was to literally soak each stone in it before installation. For now, I just shop-vac the coping/deck occasionally and the cleaner picks up the stuff that falls in the pool. Not sure I want to pursue anymore remedy for now. I've been told the only permanent fix is to replace the natural stone with something artificial (bricks, tile, etc. designed for pools). I would not recommend any natural stone for a pool to anyone.
Lastly, all this info is a few years in the making. There may be other products, methods, applicators out there today. If you discover anything, let me know. Good luck,
rpoldervaart
08-25-2011, 10:43 AM
Over the past year, the stone has begun to degrade again. The stone guy told me the best method to apply the products was to literally soak each stone in it before installation. For now, I just shop-vac the coping/deck occasionally and the cleaner picks up the stuff that falls in the pool.
Getting 4-5 years of help is good. Do you think it would help to use the drytreat again?
jonnymac
08-25-2011, 11:17 PM
Getting 4-5 years of help is good. Do you think it would help to use the drytreat again?
Yes, I think I would probably get at least the same results. The applicator said the DryTreat was actually pushing the old sealer out of the rock as it soaked in, so since the rock has had no treatment since then, it may be even better second time around. At that time, DryTreat had more than one product for the same fix (one was applied, then another, etc.) Note: Some of it will get in the water causing moderate foaming, maybe some cloudiness, etc. In my case, the stone had to be hosed down several times as the old stuff came out of the rock surface. It cleaned up fine after a few days.