A few chlorine questions

[houston_tink]

Let's say I am about to run a chlorine/pH check and am distracted by small child shenanigans....after how long is the test deemed invalid? In other words within how many minutes do I have to read it to get accurate results?

I run my filter during the day but want to add chlorine in the evening...I assume pump needs to be on to circulate it though, right? Suggestions on timing?


My last full test results were 7/15
FC 2ppm
CC 0
CH 175ppm
TA 70
CYA 45
CL 3
PH 7.8

Tummy bug struck and didn't test until yesterday morning and no chlorine. So I dumped a whole jug of 8% concentrated chlorine in the pool (per pool math recommendation) and tonight my chlorine is 5 and pH 7.8. How do I know how much chlorine to add each night to keep it at 5? Any bright ideas on an easy way to measure out chlorine without making a mess?

 

[mknauss]

The pH test is OK for some time. The FAS-DPD test is one that only is good at the end point. If you let it set it will turn pink again.

You test so that you know how much bleach / LC to add each night. As far as measuring, with your size pool, I would think you will be adding at least a gallon a day during the summer so no real need to measure. If you need more, dump a partial bottle in too. No real need to get that perfect.

You should let the pump run for 30 minutes or so after adding to mix it in.

Take care.