CCL Calcium test - Standard vs. Sensitive

[samjesse]

Hi
The Clear Choise Lab kit booklet has two pages to test the CH level. One page if CH is expected to be >100 ppm and the other page if TA is expected to be <100 ppm.
Well, I am expecting both as the PoolMath logs show.
So which would be a better choice? I just sprinkled 1K and will need to buy 4K more next few days to put in a cloth and place it in the skimmer basket.

PoolMath:
Recommended 250 - 650
Ideal 350 - 550
which tells me a target of 450 is what I need to aim at. an addition of 5kg of Calcium Chloride as per PoolMath suggestion.

Thanks

 

[Costas > DownUnder]

The calcium hardness test can be run on a high or low sensitivity basis.

The high sensitivity test just requires the use of more chemicals to obtain a final reading.

Doesn't really matter which one you use but for lower overall CH values, the more sensitive test will provide the user with a more accurate result due to the increased droplet resolution offered by the more sensitive test.

However don't get hung up on absolute accuracy for CH - doesn't really matter if you are out by, say for example 25ppm.

I prefer to maintain my CH average around the 300ppm mark but it does vary due to filter back-washing, rain and freshwater filling in summer.

My CH varies from around 250ppm up to 350ppm depending on which time of the year I am managing it.

 

[mgtfp]

You don't need to aim to be bang in the middle of the ideal range, anywhere there is fine. The ideal range is already the middle of the acceptable range. The range is there to cover for different boundary conditions. If someone for example has high calcium in the fill water, then there is no point struggling to get down to 450, in the same way as there is no need to add lots of calcium chloride to get up to 450 for someone with really soft water (like lots of Aussies have). In the end you want balanced water that doesn't lead to calcium scaling or plaster damage in concrete pools, or vinyl liner damage, etc.

I usually try to be somewhere between 300 and 400. More towards 400 in winter to compensate for low temperatures reducing the CSI to protect my plaster, in summer I allow it to get down closer to 300 before I correct.

And as Costas already mentioned, 25ppm accuracy is absolutely sufficient for CH. No need to waste reagents on the high accuracy test. For TA, where I want to hit a 20ppm wide ideal range, I usually prefer the higher resolution test.