Green Water

[Garret]

In the last few days my water has turned from clear to green.
Added 2 gallons 10% bleach yesterday.
Pool is open all winter.
Following is test levels from today.
PH 7.6, TC 5.0, FC 5.5, CC 0.0, CH 250, TA 100, CYA 90
Any suggestions are greatly appreciated.
Thank you.

 

[Nagorg]

With CYA of 90, you need to raise your TC to about 10-12.

Pool School - Chlorine / CYA Chart

 

[Texas Splash]

Actually Garret, I'd go a step further and give you this to think about .... Green water = algae = "SLAM" which at a CYA of 90 requires an FC shock level of "35". Can it be maintained and done that way? .... absolutely. Or ..... you could exchange some of that high CYA water to bring the CYA down to about 60 or so which would require a much less shock FC as noted on the Pool School - Chlorine / CYA Chart. Either way is fine and up to you, but it is critical you maintain that required FC level until you pass all 3 SLAM criteria. Always refer to the Chlorine/CYA Chart. Remember to adjust pH down to about 7.2 BEFORE increasing the FC. That's very important. Make sure to follow the directions on the SLAM page (link below) for best success. Good luck.

 

[duraleigh]

Hold on for a bit. Did your water turn to clear green within a short time or did it get dull and turn cloudy green? That could be two entirely separate causes. Got a pic?