Trouble Keeping Chlorine

[Mjbrowny21]

My pool water is crystal clear but I’ll having issues maintaining FC. This morning I checked and I was at around 1ppm so I added 2 gallons to get it to around 10ppm. I checked the FC 6 hours later and it was basically gone.

pH 7.0. I have since added ph up
Fc .1
Tc .2
Cya 54
Alkalinity 93

Thoughts on what’s eating all my chlorine? Lots of rain lowered my cya to 5 but added cya on Monday and now it’s at 54. Thanks!

 

[PoolStored]

Algae.

How are you testing your pool Water?

 

[Mjbrowny21]

I had the pool store test it this time for the better accurate cya test vs the black dot visual test.

 

[TinFoilHat]

The manual tests that you perform will be more accurate, generally, than a pool store. Since you mentioned the black dot you have a K2006 or TF 100 or pro testing kit?

 

[PoolStored]

There accuracy is worse. Use your kit. Post a full set from your kit.

Do this test tonight. Link-->Overnight Chlorine Loss Test

 

[Mjbrowny21]

I did the OCLT and went from FC 10 to 7
Ph- 7.4
Cya- 55
Alk - 90

 

[Texas Splash]

went from FC 10 to 7

Unfortunately that is a fail result. Time to start the SLAM Process. Follow that page carefully and you should do fine.