Help! water turned green

[Kriselliott24]

24" round above ground, water was beutiful and testing was perfect all year. Went on vacation for just one week and came home to green water. I usually only test it once a week anyway. Have been testing it every day and treating per the test results, vacumming, backwashing, brushing every day also. Still looks green. Today's results and recommendations don't make sense to me.
FC 10.0 recommend 23.0-33.0
TA 240 target 50-90
pH 7.5 target 7.2-8.0
CH 200 target 0-650
CYA 300 target 30-60
Why would it recommend FC of 23-33??? When we came home from vacation, the first test showed FC of 4 and recommended range of 10-12. It's a moving target and 23-33 seems ridiculously high.
We have also drained about six inches of water and refilled it per the CYA recommendations and that went up.
Thanks for any help.

 

[Bperry]

24" round above ground, water was beutiful and testing was perfect all year. Went on vacation for just one week and came home to green water. I usually only test it once a week anyway. Have been testing it every day and treating per the test results, vacumming, backwashing, brushing every day also. Still looks green. Today's results and recommendations don't make sense to me.
FC 10.0 recommend 23.0-33.0
TA 240 target 50-90
pH 7.5 target 7.2-8.0
CH 200 target 0-650
CYA 300 target 30-60
Why would it recommend FC of 23-33??? When we came home from vacation, the first test showed FC of 4 and recommended range of 10-12. It's a moving target and 23-33 seems ridiculously high.
We have also drained about six inches of water and refilled it per the CYA recommendations and that went up.
Thanks for any help.

Where did you get your test results? The reason for the higher chlorine is your CYA results being over ~60ppm. The higher the CYA gets, the more chlorine you need to keep the water clean. That’s also the likely cause of the green water.

The only way to lower the CYA to ~70ppm is to replace 75% of the water. Draining a few inches isn’t going to do very much.

 

[Bperry]

This link will help explain the CYA/FC relationship.

The Free Chlorine and Cyanuric Acid Relationship

Managing your cyanuric acid and Free Chlorine levels is key to stabilizing your pool. Learn how these two items affect each other.

www.troublefreepool.com

 

[Kriselliott24]

Where did you get your test results? The reason for the higher chlorine is your CYA results being over ~60ppm. The higher the CYA gets, the more chlorine you need to keep the water clean. That’s also the likely cause of the green water.

The only way to lower the CYA to ~70ppm is to replace 75% of the water. Draining a few inches isn’t going to do very much.

Thank you for your help.

 

[kellyfair]

If those are pool store test numbers, there is a seriously good chance they aren’t accurate. If you don’t already have a good test kit, please get one.

Test Kits Compared

If you do have a test kit, how are you coming up with CYA of 300?