Total Hardness Results in 6-Way Test Kit

[Elwood5487]

Hello TFP friends,

I purchased a HTH 6-Way Test Kit, and here are 5 of the 6 results;
Total Chlorine = 5ppm
pH = 7.6
Alkalinity = 80ppm
CYA = 40ppm

My question is related to the total hardness results. The test calls for 5 drops of the hardness indicator and it should turn red if hardness is present. I'm puzzled by what I should be seeing and what the results might indicate.
When I add each drop it turns red momentarily and when I swirl it disappears. It takes 10 drops (instead of 5) for the water to fully turn red (more like a bright magenta), and 15 drops of the titrant to turn blue.

My pool has a 25 gauge vinyl liner. My water looks and feels great. If I drop my chlorine just slightly to get it in the ideal range could that be enough to impact the TH? And, also, do I need to be concerned about this anyway given I have a vinyl liner and not plaster? The sheet says low total hardness will cause foaming and damage plaster surfaces (neither of which I have).

Thank you as always!

 

[mknauss]

Low CH is of no consequence to you with a vinyl liner. If you see foaming, add 50-100 ppm calcium. You can use calcium hypochlorite to add your chlorine and that will add calcium.

Not sure about the test. That is not a recommended test kit. Also be ware that your chlorine test is TC only and I suspect 5 ppm is max. So that will become an issue if you have any algae or water clarity issues.

 

[Elwood5487]

What test kit do you use or what should I look for in a kit?

 

[mknauss]

I suggest the TF-100 A proper test kit is needed to get the accurate water chemistry results needed to follow the TFP protocols.

 

[Richard320]

Since it turns red with 10 drops, I suspect the indicator is bleaching out from high FC. Yes, it's not really all that high at 5 (could even be higher, you know) but lots of people who should know better still preach 1-3 FC is ideal no matter what the CYA is. But I digress. It goes blue at 15 drops, so there's your CH reading. Multiply by whatever factor. If it's low, who cares? You have vinyl not plaster.

 

[TishTash]

Not sure about the [HTH 6-Way] test. That is not a recommended test kit.

Actually, the HTH 6-Way (drop) test kit is actually suggested in the following article:

Guide for Seasonal/Temporary Pools

Smaller seasonal pools can see just as much enjoyment as their larger counterparts. In this guide we'll show you how to maintain your temporary pool.

www.troublefreepool.com