CC Question

[Z7What]

Since I started with TFPC I have always had a CC of 0. The last few days the rain has been crazy. Yesterday I added a tiny extra acid because I knew the rain last night and today was going to be a lot.

Today I checked the levels. I had a pH of 7.4-7.5, FC of 4.5, CC of .5, and adding them together I get a TC of a 5.

The only thing I did different was added 36% HCl from work instead of store bought 31.45% MA. Could the chlorine in the HCl cause the .5 of CC? Or is something else screwing up?

Wayne

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Also I noticed that Pool Math has changed a while back and never knew why.

Notice after 12 it says "trade" what does that mean?

Wayne

 

[Defgufman]

The .5 cc is nothing to worry about . Probably rain stuff

 

[tim5055]

I will quote from Jason about "trade"-

That feature is new this week.

There are several different standards for measuring the concentration of bleach. Household bleach sold in grocery stores is sold by weight percentage (typically 2% to 8.25%), while liquid chlorine sold by pool stores and cleaning supply stores (typically 10% to 15%) is sold by trade percentage. The two numbers, weight and trade, are fairly close together, but differ just a little because they are based on different historical ways of measuring concentration. I recently updated PoolMath to distinguish between them so it would have better accuracy for higher concentrations of chlorine.

 

[Z7What]

The .5 cc is nothing to worry about . Probably rain stuff

Thanks, im just nervous about it that's all. I don't test CC or TC often and yesterday when I tested it I was shocked to see I had some. I been targeting FC @ 6 and in over 2 weeks it hasn't dropped below 4. What could cause it, or cause a false reading.

I will quote from Jason about "trade"-

Thanks!

Wayne

 

[Patrick_B]

Anything that's gotten into the pool. Body oil, bugs, basically anything organic pretty much. At one drop to clear it, it's pretty much <0.5 on the 10mL test. If you can tell one drop is going to clear it, don't waste the drop if you don't want. If you ran a 25mL test, I bet it would still clear with a drop, so that would technically make it 0.2. So, Virtually Nothing....

You can keep it this much or less by running your FC at the top of the suggested range if even this amount bugs you, but you really have no worries where you are.

 

[Z7What]