Large Salt particles clogging up SWCG

Sep 7, 2012
25
So I converted to salt just over a year ago, and ever since that conversion I've had issues with large salt particles collecting at bottom of pool, inside filter, and most annoyingly in my SWCG. These are large enough particles to where to can see them at night when the light is on coming out of the returns.

Yes, my CH levels are within range, actually on the low end, and those are tested using the kit everyone recommends here.

I used pool salt, specifically Morton's pool salt, to originally add salt to my pool, and that's the only I can pin the cause of these large salt particles.

Is this what's causing this? Just bad salt? Anyone have any experience with this or any other ideas?

I just got a new filter and this one doesn't grab the large particles as well as the old one, so now I am forced to clean my SWCG once a week as opposed to once a month with my old filter, which is just ridiculous.

So, I'm thinking a drain and refill is the only fix for this? I'd hate to do this and the salt not be the cause of this, but I honestly can't think of anything else. Any and all help or ideas are appreciated.
 
This has nothing to do with the salt or the filter. This is calcium buildup which is caused by a combination of high CH and high pH. What do you target for pH? Does it drift up? How often do you check it? How often does it get over 8?
 
My CH is fine, well within range, last time tested was 220, my PH was 7.8 this morning. Yea, sometimes it gets over 8, but not often I'd say. And yes, it does drift up for sure. I usually target 7.6.

See pool details below, if I did the signature thing right that is.
 
maybe try tasting a particle if you're willing and see if it tastes like salt? but i agree salt would dissolve almost instantly after you put it in originally. even sea water doesnt have salt particles in it.

are the cartridges installed properly, you would think a cartridge would be just as efficient at large particles and small ones?
 
What is your Total Alkalinity (TA)? The combination of pH, CH and TA is likely too high since the pH at the hydrogen gas generation plate in the SWCG is very high so calcium carbonate can form. When the polarity of the cell reverses, such buildup flakes off the cell and you get these flakes in the pool. You can manage this by keeping the saturation index slightly negative and you can further manage it by using 50 ppm Borates which will cut down the pH rise in the salt cell roughly in half.
 
I'll join the chorus that it's not salt.

But I have much higher CH than you and my pH typically rises to the upper 7s or very low 8's before I bring it down to around 7.4 or so every week with about a quart of MA. I have high TA fill water so I can only really lower my TA to about 70 and along with my large pump, spill over spa, and SWG I'm always adding MA. While my CH is much higher than yours (450-500 usually) and my pH rise is similar, I've never had calcium scale accumulate in or on my pool or in my SWG. I just checked my cell last week and it's as clean as the day I installed in 3+ years ago.

edit: I just saw Chem geek's post. I use borates and try to keep my TA below 80. My CSI typically runs no higher than .2 until I lower it each week down to around -.2 after I add MA. So it probably averages right around 0.00. So far so good.
 
Thanks for the help everyone.

What is your Total Alkalinity (TA)? The combination of pH, CH and TA is likely too high since the pH at the hydrogen gas generation plate in the SWCG is very high so calcium carbonate can form. When the polarity of the cell reverses, such buildup flakes off the cell and you get these flakes in the pool. You can manage this by keeping the saturation index slightly negative and you can further manage it by using 50 ppm Borates which will cut down the pH rise in the salt cell roughly in half.

Ok, I know that my TA definitely gets high, and my PH does too from tiume to time go over 8 if im not on top of it. Which I try to be, but maybe not enough so.

My question is, what should I do going forward? Just add a bunch of MA to lower the ph and TA really low? Say target the PH to 7.2? Or am I beyond this measure to fix it? Do I need to do something else?

The fgill water here is super high in TA, so its a challenge from the get go


I just checked my cell last week and it's as clean as the day I installed in 3+ years ago.


I'm super jealous of this statement.
 

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Thanks for the help everyone.



Ok, I know that my TA definitely gets high, and my PH does too from tiume to time go over 8 if im not on top of it. Which I try to be, but maybe not enough so.

My question is, what should I do going forward? Just add a bunch of MA to lower the ph and TA really low? Say target the PH to 7.2? Or am I beyond this measure to fix it? Do I need to do something else?

The fgill water here is super high in TA, so its a challenge from the get go





I'm super jealous of this statement.

You might give the borates a try as check geek suggested and follow his advice on the CSI. Lowering pH and TA can do wonders in battling high CH (but yours isn't even that high, which is puzzling to me).

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Another thing. How are you testing? If you are not doing your own test with a good test kit your CH (and other things) could be way off. The pool store's CH test was always 150-200 lower than the result I got with my TF-100. After several trips to the pool store to "confirm" my tests I finally just gave up and trusted my own test results.
 
As it says in the Borates information/discussions, be sure to get both your TA and Ph where you want them before adding Borates. So that would be 70-80 with a SWG and Ph of 7.4 to 7.6. From what I read, the stabilizing effects you get from Borates (which you want) also makes it more difficult to change TA in the future.
 
Yes, the link above has everything. It's pretty simple, actually. You can buy (expensive) products mentioned in the link above or do it inexpensively by adding the correct amounts of Borax and M.A. IN THE CORRECT ALTERNATING SEQUENCE (not just randomly dumped in all at once) outlined in the instructions.

I did it last year. Not scary.
 
Or you can buy Boric Acid from Duda Diesel or The Chemistry Store (or possibly AAA Chemicals). You only add one chemical in this case and the pH doesn't swing up and down as a result. It used to be more expensive, but now is much closer in price to the Borax and Muriatic Acid.

However, we still don't have a full set of numbers including the TA level. CH is 220, pH is 7.8 or higher (7.6 target, but gets to 8.0 or more), being an SWCG pool I presume the salt level is around 3000 ppm, but what is the TA level and also the CYA level? If the TA were 100 ppm and the pH 8.0, then the saturation index would be +0.1 in the bulk pool water, but significantly higher in the salt cell. It would be better if the TA were closer to 70 ppm if the pH is going to get higher at times.
 
Or you can buy Boric Acid from Duda Diesel or The Chemistry Store (or possibly AAA Chemicals). You only add one chemical in this case and the pH doesn't swing up and down as a result. It used to be more expensive, but now is much closer in price to the Borax and Muriatic Acid.

However, we still don't have a full set of numbers including the TA level. CH is 220, pH is 7.8 or higher (7.6 target, but gets to 8.0 or more), being an SWCG pool I presume the salt level is around 3000 ppm, but what is the TA level and also the CYA level? If the TA were 100 ppm and the pH 8.0, then the saturation index would be +0.1 in the bulk pool water, but significantly higher in the salt cell. It would be better if the TA were closer to 70 ppm if the pH is going to get higher at times.


Ok, I retested, I was off on the PH this morning,
FC = 3.5
CC = 0
PH = 8.1,
TA= 210,
CH = 150
salt = 2700 (guess, salt measurement tests are always off, I just add salt until my SWCG stops flashing at me)


My CH has got to be higher right? That test is weird, I still see faint red at the top of the water after 15 drops yet the majority of the water seems light blue. CYA is around 5. Yes I know my CYA is low, I don't bother with it as I have a slight leak (1/8" a day) and an auto cover and my chlorine stays high running the SWCG at the lowest setting, 20%, because the pool is covered 90% of the time and I don't mind if the sun drains out some chlorine. I have to refill every week or 2 a few inches and I don't feel like messing with socks and dissolving cyanuric acid every few weeks when I don't care if the sun saps the chlorine. The chlorine is higher than normal right now because it was at zero 5 days ago b/c the cell was off due to the deposits, I didn't catch that for a couple days so I boosted the SWCG for 24 hours and the pool hasn't been used since. It's usually at a 2-3.
 
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yes, definitely right.... it could be higher even, its dark yellow

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btw, im about to add a gallon of acid per the pool calculator to lower my TA and PH

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also, I just looked on the tfttest kits site and for the CH test it says multiple by 25, yet on the laminated sheet i got with the kit it says multiply by 10... any idea which one it is? http://tftestkits.net/Test-Kit-Instructions-10.html
 

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