Home test results vs Leslie's

[bmlshield]

Newbie here. I've had my pool for a whole 3 weeks now and my head is spinning as I get my TFP bachelors degree in chemistry.

I'm trying to figure out what shock level I need to get to for treatment. Id rather move to liquid chlorine rather than keep buying powder from the big guys. Based on my results they are suggesting 5lbs per treatment in my 37k gallon chlorine pool. My last test from "Leslies Bank & Loan Co" was the following:
pH 7.4
ALK 100
CYA 80
FAC 2
TAC 2
Po 100
CH 250

When I test my FC at home I have been north of 5 every time. Following the instructions on my F-1004 exactly. As a matter of fact I have never been below the darkest pink reading 5 Cl and 10 Br shade. Color might look off in the pic but I have circled the closest match.

 

[mknauss]

Welcome to the forum!
You need to follow the SLAM Process. To do that, you need a proper test kit, see Test Kits Compared. I suggest the TF-100 Test Kit ™
While you are waiting on your test kit, add 5 ppm FC worth of liquid chlorine / plain bleach to your pool each evening with the pump running.
I suggest you read ABC's of Pool Water Chemistry and consider reviewing the entire Pool School eBook.

 

[jimbethesda]

Also, the test you are using measures total chlorine, not free chlorine. So that test is telling you that you have at least 5ppm of total chlorine....in other words, it doesn’t tell you anything useful. You need a FAS-DPD test that is included in the test kit above.

 

[Jimrahbe]

B,

You can use this chart to figure out what your SLAM level should be.. FC/CYA Levels

I notice that your CYA is 80, which makes performing a SLAM more difficult because of the high level of Chlorine you need to kill your algae.

I suggest that you drain about half your water and then do the SLAM...

If you don't have one already, you should get a test kit that can measure FC up to 50 ppm.. I use and recommend the TF-100 and Speed-Stir...

Thanks,

Jim R.