Can't Get Free Chlorine Levels Up

[dakstn]

I have a 21' round above-ground pool with a Hayward earth filter. I opened it 6 days ago and added about 1' of water to bring the level up to normal. I winterized when I closed it in the Fall and the water has been clear since I opened it. I use a chlorinator with 3" tri-chlor pucks.

I don't yet have the TF-100 test kit - just ordered it today. I do have a basic OTO test kit as well two different test strip kits (AquaChek and Clorox brands). My current test results are:

AquaChek 6-in-1 Test Strips
Total Chlorine: 3
Free Chlorine: 0 (between the 0 and 0.5 colors)
pH: 6.8
Alkalinity: 120
Bromine: 3
Total Hardness: 250

Clorox 6-Way Smart Strips
Total Chlorine: 3
Free Chlorine: 0 (between the 0 and 1 colors)
pH: 6.8
Alkalinity: 120
Stabilizer: 25 (somewhere between the 0 and 50 colors)
Total Hardness: 250

OTO Test Kit:
Chlorine: 0.5
pH: 6.8

I've been trying to get the Free Chlorine up. Spread out over the days since I opened, I've added 2 1/2 gallons of liquid bleach (7%), 3 lbs of cal-hypo shock, 4 lbs of dichlor shock, and 5 lbs of non-chlorine oxidizing shock. I've also been vacuuming and brushing multiple times each day. Nothing I do seems to bring up the Free Chlorine.

My questions are:
Is it safe for kids to swim now?
What should I do until I get the test kit?

Thanks for any suggestions.

 

[ajw22]

Welcome to TFP.

21 foot round is maybe 13,000 gallons. Please create your signature with details of your pool and equipment.

Each gallon of 6% bleach adds 3 ppm. So you added about 7 ppm of chlorine from the bleach. 2 lbs of cal-hypo is around 9 ppm depending on the %. 4 lbs of dichlor shock adds 13 ppm of chlorine.

In total you added around 29 ppm of chlorine. You pool may lose 2-3 ppm of chlorine a day.

Does this convince you that your test strips ae junk and should be trashed?

The problem is we don't know what your CYA is to say your chlorine level is safe.

You should stop throwing chemicals into the water without knowing what the effect should be. PoolMath will calculate it for you.

You should wait until you get your test kit. What did you order?

 

[dakstn]

Thanks for the response. I ordered the TF-100 kit. I'm not ready to throw out my strips just yet just because those and the OTO drops are the only tests I've used over the past 10+ years of owning the pool. Typically I open the pool and treat with a couple bags of shock and the pH and chlorine levels move into the recommended ranges. After that, I add chlorine tablets as needed and test the water weekly to be sure pH and chlorine are in range. This is the first time I've not been able to get the free chlorine to show up and from what I've read here, it seems that the way to get the free chlorine to come up is to add more chlorine.

If the stabilizer number on the strips is to be trusted and does represent my CYA, then it's somewhere between 25-50. I'll wait for the TF-100 kit, but it probably won't arrive until the end of the week. I just wanted to know ask what I might do until then to safely let the kids swim.

 

[ajw22]

See the FC/CYA Levels. Any FC up to SLAM level is safe to swim. At CYA 50 that would be FC of 20.