Total Alkalinity ("Input" versus "Adjusted")_What Is The Difference

[mmcwhorter]

My local pool store (where I usually buy Muriatic Acid) has a free water test using a system I believe is called "poolife Exclusive Pool Care Collection". In the output of the test, they have TA measured as both Input and Adjusted. What is the difference? My TF-100 measures much closer to the Input number, which today was 76...and Adjusted was 51...in which the computer print out prompted me to buy something even though it said I had a CSI of 0.00 (first time THAT ever happened).

The readings from the pool store today are:
FC: 7 / CC: 1.67 / PH: 7.5 / TA 76 and 51 (input and adjusted) / CH 253 / CYA 75 / Phosphates: 1571 / Salt 2737

Since I can't measure Salt, that's usually why I go there 2x per season to do a check, even though my SWG has Green/Good for the Salt. My TFT-Readings were within reason of their except as noted below...

TFT-100 CH reading is more like 325-350, and one other thing: I consistently measure less than 0.5 ppm for CC, every time for the last 3 months...so I really call in to question the reading they provide. And of course, I was encouraged to "Shock" as a result.
The ONLY time my CC is high is when we pull off the cover. Once I do a SLAM, it's good all season. Most times, it's immeasurable.

I have one more 40-pound bag of Pool Slat, I think I'll dump it in later today to likely get me by for the rest of the season.

 

[YippeeSkippy]

Here ya go-- last paragraph

TA - Further Reading

www.troublefreepool.com

 

[Texas Splash]

I really call in to question the reading they provide.

Exactly! That right there is why we avoid the pool store. If we ever do go there for something, take the printout, laugh, ponder, toss it in the trash, whatever you want, but don't second-guess your own reliable TF-100 results. Store testing will almost never match yours and you can just about bet they will change their results the next day or even a few hours later if you went back with another sample.

Also, the PoolMath APP is programmed to do any/all auto-adjustments for TA-CYA. All you have to do is enter your own numbers. Easy stuff.

 

[mmcwhorter]

Ah, never saw that before, thanks. As I said, they are close by the house and good for MA purchases, and I have come to trust their salt readings also (which I can do)...they correlate well with my SWG green light going red for Salt Level. I admit when there are uneducated folks in front of me being told to buy all this other stuff (flocculants, clarifiers, etc...) I felt like I should follow them out to their car and point them to TFP.COM.

 

[mmcwhorter]

by the way, I have a lot of 3" trichlor tabs sitting in cool/dark storage, probably 3-4 years old. I NEVER use them...except: My CYA was around 50-55 recently, felt it was Ok but on the low side of good.... and I had no Stabilizer left..... So I put the tabs to good use. I thought CYA should be closer to 70 for my Salt pool...Pool math said to add 5 tabs and boom...it's 70 now. Took 10 days for it all to dissolve in floaters, but it worked. Love it.

 

[YippeeSkippy]

I felt like I should follow them out to their car and point them to TFP.COM.

Well, actually...you can get some business sized cards advertising the forum from TFTestkits.net I believe? Hand those out.

 

[Texas Splash]

So I put the tabs to good use. I thought CYA should be closer to 70 for my Salt pool...Pool math said to add 5 tabs and boom...it's 70 now.

Perfect! That's what TFP is all about.

 

[mmcwhorter]

Ah, biz cards for TFT...a great idea. I really do tell interested folks who need to know about it all the time. I think they'd really get ****** at me if I did it to a Pool Store Customer on the way out the door.

 

[Katygreys]

I wonder if the water testing computer at the pool store is tied into the P&L in SAP. They could use AI with inputs of local weather, UV index, product cost, historical revenue trends etc etc. Then, when the AI detects conditions ripe for an impending decrease in revenue…BOOM, it starts outputting results that require magic PS potions. To wit: @mmcwhorter has always measured 0 CC, but the PS machine mysteriously (or perhaps not so mysteriously) output a value of 1.67. Just enough to cause alarm and make a sale, but not enough to be completely outrageous.

If this is not actually happening, I call dibs on the technology and will take my idea to market ASAP!!

 

[mmcwhorter]

Kinda feels like "planned obsolescence" with automobiles...no act of malfeasance these days would surprise me.