CYA dropped and so did free chlorine

Pajara

0
Jan 6, 2019
23
Tucson/arizona
So my CYA dropped to less than 20 after a long hot summer and now my free chlorine is only 0.5 and total chlorine 1.0. I have added CYA and it is now back up to 40 but my SWG has not raised the chlorine levels in a week. Any suggestions? Just cleaned the cartridge filter and salt cell today. Should I drop in a couple of pucks of chlorine to raise the levels back up. Chlorine level was good all summer with just the SWG cell providing it until the CYA dropped.
 
The SWCG is not designed to raise your FC levels. I suspect you have algae.

I suggest doing a Overnight Chlorine Loss Test. Add 10 ppm FC worth of liquid chlorine, circulate pool for 30 minutes, test FC, and then test FC in the morning before sun hits the pool surface.
 
So I am at TH=250, TC=10, FC=7, pH=7.2, Total alkalinity=60 and CYA=50
If the chlorine levels stay the same over night am I okay? I know the pH is low but the pool is only 6 months old so I know the pH will creep up again. We had a lot of rain in the last month and the pool was running at 88 degrees so I know I will need to stay on top of it during monsoon season in the future.
 
Is TH actually CH? The difference between TC (which I assume is total chlorine) and FC is 3 which isn't good and you probably need to do a SLAM as your CC levels indicate you have an algae issue.

What test kit are you using?
 
Using Taylor K-1001 for free chlorine and pH and Taylor K-1000 for total chlorine. Checked levels again this morning for the overnight chlorine loss test and both my free chlorine and total chlorine are at the top of the color range so it looks like they are both reading 10 and the pH is still 7.2
Also did a quick read with AquaChek Select strips and got the same results. Looks like the CYA is between 50 and 100 on the strips.
Do I still need to SLAM?
 
If you need to follow the SLAM Process, you need a proper test kit, see Test Kits Compared. I suggest the TF-100 A proper test kit is needed to get the accurate water chemistry results needed to follow the TFP protocols.

You cannot manage pool water chemistry with the kit and strips you have.
 

Enjoying this content?

Support TFP with a donation.

Give Support
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. This will replenish the FC lost each day to the sun and also inhibit any algae in the water from growing further.
 
You need to get the C version of the K2006.

A better value is the TF100 from TFTestkits.net.
 
Finished my SLAM, kept FC at 24 for 3 days, CYA was 50. Now CC=0.5 and OCLT was 1.0, water is clear can see heads on a quarter at 5 ft. 2 days latter Current test is CYA=50 TC=15 FC=15 pH=7.2 Total alkalinity=40 and CYA=50. Water temp has dropped to 83. I know my CYA level is low for a SWG pool, 70-80 recommended?
Which chemical should I adjust first Alkalinity or CYA level?
 
What is your CH? You can add 20 ppm TA worth of baking soda. How did your TA get so low?

No real need to raise CYA right now as we are entering winter. Just maintain your FC at 4 ppm or above with your SWCG until it stops producing for the winter then add liquid chlorine as necessary.
 
MY CH is 300 which from what I understand is what to expect in Tucson AZ, we have really hard water. Fill water is at 250 out of the tap. We had inches of rain (lots of dirt in it from our dusty skies) and that is when the chemicals went out of balance. I probably got a little over zealous with the acid at that point. We still have swimming weather here 95 degrees so should I bump the CYA up a little too.
 
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.