Should I Target a Lower CH Level?

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Leave the CH alone until you get the TA where you want it.
After the TA is under control, let pH rise to 7.8 and check your CSI again.
Then, if CSI is out of range, adjust CH.

Trying to do too much at once will only cause a roller coaster effect and frustrate you.
Having CSI out of range for a week or two won't cause any big issues.
 
True.

I aerated the pH to 7.5 then quit and will probably add a bit more MA to get the TA down to 80. According to the math that should bring csi to a bit above -0.30.
 
Your signature does not show it but if I remember correctly you use softened water for fill water?

If so, just use non softened water to fill the pool every once in a while (you can over fill be an inch or so).
 
So I over-shot a bit and TA is at 70 with pH at 7.5. I know the pH will rise by itself but what about TA?

I have Arm and Hammer baking soda (aka sodium bicarbonate) on hand but do I need to add it or will TA rise naturally?
 
Understood. This pushed my csi to -0.62 so that's a bit concerning.

If my water has all minerals but residual salt of about 50ppm or less where's the Alkalinity coming from?
 
My fill water goes through a sand filter to remove solids, carbon activated filter to remove chlorine and flourine and ion exchange to replace all the "ium's" (calcium, magnesium, etc) with sodium at a low concentration. The only source of calcium to raise TA in my pool would be plaster if I am not mistaken.

Some sources say csi between -0.60 and 0.60 which I'm pretty close on the low end. Other sources say -0.30 to 0.30 which I'm out of range currently. Which is better?
 
Alkalinity is not removed by a water softener.

Occasional lower CSI is not a big deal. It will rise as the water temperature rises. Let the pH rise to 8+ before addressing.
 
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I'll stay out of the fray of pH and TA, you're getting good advice there. Just some observations...

Add your softener hook up to your signature, something like mine.

You likely are not auto-filling with zero-CH water. I thought for sure I was, but my CH crept up over the last few years to the point where I had to do a water exchange to bring my CH back down. Of course, I made the mistake of doing so last fall, and then we got all the rain, but it's still around 325, so I'm good.

The CH rise is a bit of a mystery, but I've got a strong theory. I don't think it's leaching out of my plaster, because my CH started at about 350 and got up to over 500. At some point there would have been plenty of CH in the water and any leeching would have stopped. So from where then?

I, too, can test my softened fill water and get zero CH. But it's probably not zero, it's just not registering. So with our very active evaporation, we're putting upwards of 100 gallons of water into the pool a day, and so some amount of CH each day. As you know, CH won't evaporate out, so it's going to collect. And on your craziest swim days, I can't imagine your splashing 100 gallons of water out of your pool each day, so you are collecting CH, even from softened water. And even with crazy splash out, you'd be refilling with the same low-CH water, so you would not lose much CH, you'd just be breaking even. Except...

The other likely source of CH is from the unsoftened water you're adding some number of days each week. Between the pool and your family, your water softener is probably regenerating somewhat often. (Do you know how often?) Every time it does, it goes into bypass mode for a few hours while it does its regen thing. Well, when your auto-filler kicks on while your softener is in bypass, it'll be drawing water from the street, with all the CH and TA goodness your city provides. And that CH will collect, too.

Point being, you're very likely not auto-filling with CH-free water. Do what you're going to do with pH and TA, and if you then determine you want to add a little CH, add only the bare minimum to make your CSI happy, because you shouldn't assume it's not going to rise, it likely will. If CA continues to have decent winters, your CH will probably stay stable, as mine did for the first few years, because each winter you'll get a free water exchange. But if (when) we go back into drought mode, you won't get enough exchange, and so your CH will rise and you'll eventually need a manual exchange. Mine took several years to get too high, but it did.

I've addressed my softener bypass issue, and will eventually explain how I did it in a thread I've yet to write. I'll keep it updated in the coming years to track my solution, which might prove my theory. Short version, I use a motorized valve and my pool automation controller to shut down the water source to my auto-filler during the hours my softener regenerates, such that my auto-filler, even if it activates during those hours, won't be pumping any hard water into my pool. So now the only source of CH my pool will be getting is whatever sneaks past my softener, which I'm hoping will be offset by my free winter-rain exchanges.
 
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@Dirk

So how does your softener communicate with you pool automation to shut the valve during a re-gen?
My US Water Systems softener (Plus Carbon Activated Prefilter) only communicates with me via Bluetooth unfortunately but maybe there's a way to hook it into home automation to control a valve. It does a regen every 10 days unless it processes more than Grain Limit of the Resin which I don't know how many gallons that equates to but suppose it varies base on the hardness of the water coming in between scheduled regens. AFAIK mine only regens on the schedule which equates to about 900 gallons per regen.
 
I think @Dirk has an inline irrigation valve plumbed between his water softener and his pool autofill.
This valve would be programmed thru a sprinkler timer to turn the valve off during the normal regen hours.

My softener regenerates at 2:30am. If I had his setup and since my softener regens after 'x' number of gallons used, I'd probably program that valve to shut off from about 2:00am to 5:00am daily. Having it set on a daily schedule would allow the softener to regen after 'x' amount of gallons used instead of on an 'x' number of days schedule.
 
Well why didn't I think of that! LOL. Just have the valve closed everyday at the regen time and then it will be shut no matter what day the regen occurs.

That said, sprinkler valves are normally closed until the timer says to open. How do you change the polarity of the valve so it works in reverse?
 
ShallowWater said:
Well why didn't I think of that! LOL. Just have the valve closed everyday at the regen time and then it will be shut no matter what day the regen occurs.
Click to expand...
Exactly what mine does. It closes about an hour before my softener is scheduled to regen, and opens about an hour after. I also have a whole house filter that regen's every so often, about 1/2 hour before the softener, so I had to bracket around that, too.

I didn't use a typical solenoid sprinkler valve, I used a motorized valve. The primary advantage to a motorized valve is that it only uses power to move, and then it stays in position until called upon to reverse, unlike a solenoid valve which uses power the entire time it's "on." The other advantage of this type of valve is that you can buy them as normally open, or normally closed. Since I want mine open more hours than closed, I got the normally open one. My pool automation system applies voltage to it, and it closes (shutting down the auto-filling). Then it stays closed while voltage is applied, even though it's not actually using any power to stay closed. It somehow stores some energy, because when the timer shuts the voltage off, the valve has enough "juice" to open itself.

There are also normally closed versions, say, if you only wanted the auto-filler to run a few hours a day.

I also like normally open, because if the power or the timer fails, the valve will remain at, or return to open, which is what I would want if the failure occurred while I was gone for an extended period of time.

The one I found works on AC or DC, and a wide range of voltages, so I just connected it to one of my automation relays and used an AC voltage available within my automation controller. EZPZ. You could accomplish the same thing with any sort of timer and a power brick of sufficient wattage to run the valve.

 
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So I just ran pH and TA only right now.
pH = 8.2 already and TA = 70 or 80 depending on how one reads it.

I learned in Chemistry to always take the reading at the first titration. In this case at 70ppm it changes from green to some sort of greenish purple and at 80ppm it goes completely red. If I take the first titration reading TA is still a bit low at 70ppm. If I take the first complete color change whereupon adding more 0009 reagent will not change the color the TA is perfect at 80ppm.
 
I said I'd stay out of the fray, but... 50-90 is acceptable for TA. Leave it alone, it's fine. Get your pH into the 7s and TA will take care of itself.

PS. The result is the last drop before the color doesn't change, not when it first changes. So you're at 80 (full red).

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I'm not sure how high the pH tester you have goes. Mine goes to 8.0. If yours goes to 8.2, you might not actually know what your pH is. If you're getting the highest color comparison, then it is that number or above. That's the added benefit to keep your pH in the 7s, when you can compare to 7.8, you know you have 7.8. Bring your pH down to the 7s and don't let it get above 8 (or whatever your second highest color bar reads). That way, you can keep track of your actual pH. If your pH is regularly at your highest color bar (or above) when you test, then you're not testing your pH often enough. Test and dose as often as it takes to keep your pH in the 7s.
 
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Interesting..

I bought a TFTestKits pH meter but I cannot get the protective cover off it. I need to get in touch with them.

Nevertheless, when my pH was at 7.2 the other day it was obvious on the color bar for sure.
 

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