I'm a little confused. LOW CH (50-75) this year after fighting it being super high..

[mjb62676]

Since taming the swamp two years ago, almost to the day, I had always fought with a scale I couldn't get rid of. pH was high as was CH. Toward the end of last year, I finally got the gumption to dump acid in the pool and got the pH down and the scale magically went away. Winterized by shocking hard and opened to a beautiful clear pool.

The pool was nearly "full" when opening due to over 10" of rain over the winter months.

Since opening, I've had very low TA and pH. Now have TA up to 80 (added more soda this morning) and pH in the 7.2-7.4 range. Using Bleach to maintain (or try) to maintain TC of about 6 (worried about going too high due to new pool heater and apparent bleaching of deep end of liner).

But, my CH has gone almost completely away. The only reason I can think of is rain and having to drop the water, and not having to use much, if any, of my source well water, which is very hard.


What I can't tell is if I need to try to raise it. Have a vinyl liner, so not terribly worried about that, but worried about the heater and pumps, etc.

Results this morning
pH 7.2
CH 50
TA 80 (added baking soda)
TC-2 (added bleach)
CYA about 70 (will keep working to get this down as we've gone completely puck free now, had been using a hybrid of pucks and liquid chlorine from Menards)

Do I want to deal with adding calcium, or rely on evaporation and water replacement with hard water?

 

[Texas Splash]

There's really no need to add calcium at this point. The TFP Recommended Levels chart (link below) validate that as well. I suspect that when summer finally arrives, your fill water will add to that CH number anyway.

 

[cowboycasey]

I would not add any, your levels look good except FC but you said you already raised that

draining/lowering water and then rain water has dropped your CH, not a bad thing

 

[mjb62676]

Thanks.

I'm worried about why my liner seems to be fading...quickly. Opened in mid-april and there was not much fade noticeable. Surely baking soda didn't do it (I've had to add a TON of it...like 40 lbs, to get my TA up. pH was in the high 6's when I opened and has come up since adding the baking soda.

 

[mjb62676]

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[Texas Splash]

Very nice!

 

[cowboycasey]

could you have added chlorine and it did not mix in and settled in the bottom? is your liner fading or is that scaling, if scaling that could explain where your CH went...

 

[mjb62676]

could you have added chlorine and it did not mix in and settled in the bottom? is your liner fading or is that scaling, if scaling that could explain where your CH went...

The only thing i can think of is when I shocked it last fall, or when my guy that opens for me shocked it this spring, it settled to the bottom. He would have had the pump on and I'm pretty sure I had it on and brought TC way up in fall. I have to wonder if it's scale of some sort.

 

[pooldv]

Is it rough like sandpaper?

 

[JamesW]

40 pounds of baking soda in 25,000 gallons would raise the TA by 115 ppm. If your current TA is only 80, then your opening TA must have been -35, which would put your opening pH at around 4.

What is the TA and calcium hardness of your fill water?

 

[mjb62676]

40 pounds of baking soda in 25,000 gallons would raise the TA by 115 ppm. If your current TA is only 80, then your opening TA must have been -35, which would put your opening pH at around 4.

What is the TA and calcium hardness of your fill water?

I will have to check TA. CH is 300 on fill water.

My pool volume is very hard to calculate Shallow end is 3 feet deep. Deep end goes to 9 feet, I believe, but slopes the whole way. I believe I'm between 25k and 30k gallons.

Not rough at all. Last year, the scale that we saw was rough when brushing. This is smooth, so it makes me believe it is fading vs. scale.

 

[Swampwoman]

Greetings.
Your liner looks pretty good, but since you asked, It is entirely possible that in combination, shocking plus acidic environment caused a bit of fading in your hopper.

For example, slamming according to the [fc/cya][/FC/cya] chart in and of itself will not fade a vinyl liner if the TA and PH start out in range. But a low/crashed ph/TA can itself cause fading of liner print. When the two are combined and then the TA/Ph sit low for the winter, its possible this exacerbated the natural fading that occurs.

Liner quality (eg lots of reports of offshore mfg of vinyl degrading quickly, but same seem to be mentioned by virgin vinyl North American producers, so take with a grain of salt -- also is a factor.

Its also possible if your guy shocked on opening but had not recovered the ph/TA to protective range that this incident created the fading condition, and that same is being exacerbated by sun.

I know none of that helps at the moment, (though you were curious) but the best advice moving forward is to be certain to keep your TA and PH in range, particularly if slamming is in order, and of course, to avoid slamming by keeping your water to TFP parameters at all times. This will help you extend your liner's life.

 

[mjb62676]

Thank you. I think we are on the right track now. TA and pH have normalized and I'm able to keep the TC in the 5-6 range. It's been dropping to 2 or so fairly often so I'm guessing I've had some near misses. More rain today so we will see what tomorrow brings


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[mjb62676]

Thank you. I think we are on the right track now. TA and pH have normalized and I'm able to keep the TC in the 5-6 range. It's been dropping to 2 or so fairly often so I'm guessing I've had some near misses. More rain today so we will see what tomorrow brings


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Now, I'm fighting high TA (130) and high pH (approaching 8+). I suspect the bleach is the culprit as I'm having to dump a full 121oz jug in every day to maintain chlorine levels in the 5-6 range. This isn't making sense to me. CYA is in the 60 range.

 

[Texas Splash]

Actually, the bleach would have noting to do with the pH at this point since your FC is low (under 10). I suspect your pH is just rising because of the elevated TA. You're aware of the acid/aeration trick to lower TA right? Look at the TFP Pool School - Lower Total Alkalinity page for details.

As for the FC, I add 1/2 gal to my 18K pool each day. It's not unreasonable that your pool needs about 3/4 - 1 gallon. As long as you are not exceeding the use of 4 FC per day, you are doing okay. But as you have probably already learned here ....whenever you have doubt as to FC consumption, do an overnight (OCLT) test. If you pass, you are algae-free and can increase CYA a little. If you fail, you know the organic goblins are in there and you need to SLAM again.

 

[mjb62676]

Actually, the bleach would have noting to do with the pH at this point since your FC is low (under 10). I suspect your pH is just rising because of the elevated TA. You're aware of the acid/aeration trick to lower TA right? Look at the TFP Pool School - Lower Total Alkalinity page for details.

As for the FC, I add 1/2 gal to my 18K pool each day. It's not unreasonable that your pool needs about 3/4 - 1 gallon. As long as you are not exceeding the use of 4 FC per day, you are doing okay. But as you have probably already learned here ....whenever you have doubt as to FC consumption, do an overnight (OCLT) test. If you pass, you are algae-free and can increase CYA a little. If you fail, you know the organic goblins are in there and you need to SLAM again.

Thank you.