Question regarding dissolved solids

[Zindar]

Something very annoying happened...Overnight, some of the water siphoned automatically backwards through the hose, and where the hose connects to the hose bib is where it leaked out. I may roughly estimate that I lost about 500 gallons of my 7600 gallon pool.

So having learned my lesson, today when I put water in my pool, here's how I did it:

The picture probably isn't good quality, but I dangled my pool pole from my deck railing, supported by a broom stick on the bottom end, so it doesn't fall off. (the hose was hanging from the pool pole.) By the way, that deck was just constructed today.

 

[JohnT]

Way to get creative! It also makes noise so it's harder to forget about it.

 

[bridgman]

Did anyone else look at that picture and imagine a Marineland-style killer whale jumping up to eat the hose ?

 

[Zindar]

Well, I found the water quality report, by the way:

Barium				.0353 - 0.0506 ppm
Flouride			.57 ppm
Nitrate				.304 - 1.02 ppm
Dibromochlormethane		13.62   ppb
Chloroform			3.91 ppb
Bromoform			8.69 ppb
Bromodichloromethane		9.3 ppb
Chloramines			2.07 ppm
Haloacetic Acids		12.1 - 19.6 ppb
Total Trihalomethanes		29.3 - 41.0 ppb
Bicarbonate			183 ppm
Calcium				61.7 ppm
Choride				48 ppm
Magnesium			16.8 ppm
Manganese			.00251 ppm
Sodium				28.4 ppm
Sulfate				27.4 ppm
Total Alalinity as CaCO3	183 ppm
Total Dissolved Solids		333 ppm
Total Hardness as CaCO3		182 ppm
pH 				7.7
Conductivity			507 UMH/CM

Out of curiosity, I tested my water via my TF-100 kit. The water from my hose bib measures at 125 ppm CH, and the water out of my water softener measures at between 0-25 ppm CH. This seems greatly different than our municipal water quality report. Maybe I should complain to our municipality about possible inaccuracy in their reports.

Hopefully this higher level than I thought (125 ppm) won't be too unmanageable for my pool.

 

[chem geek]

The "Calcium" in your water quality report is measured as ppm Calcium, not as ppm Calcium Carbonate which is how calcium is measured in your test kit. Notice the "Total Hardness as CaCO3" on the report that is higher than yours. That is because though measured in the same units as your test, it is also including magnesium since that is part of total hardness. The water quality report does not list Calcium Hardness (CH) as CaCO3. You can convert from their Calcium level to CH as follows:

(61.7 ppm Ca²⁺) * (100.0869 g/mole CaCO₃) / (40.078 g/mole Ca²⁺) = 154.1 ppm CaCO₃ (i.e. CH)

Are you using the 10 ml water sample for the CH test so that each drop is 25 ppm? If so, then you are within one drop which is within the accuracy of the test. If you are using the 25 ml water sample for the CH test, then each drop is 10 ppm so is your 125 ppm an estimate "in between" drops?

Also, the water quality report clearly has some problems of its own since Total Hardness is the sum of calcium and magnesium in CaCO₃ units so should be:

154.1 + 16.8 * 100.0869 / 24.305 = 223.3 ppm Total Hardness, but they list 182.

So I question some of the accuracy of the water quality report that could explain some of the variation between their CH of 154 and yours of 125.

 

[Zindar]

Thank you for that very informative and interesting post. I was indeed doing 10 ml test where each drop represents 25 ppm. At the very least, this means there is no evidence to doubt that the TF100 kit is working as advertised.

I also used it to test my inside water, which is softened by my kenmore water softener: it turned blue on the first drop, and was almost blue with zero drops, so this makes me happy, as it suggests my water softener is working.