UV must be gone, time to turn down my SWG!
- Thread starter JeaniB
- Start date
With an FC of 10+ the PH test is invalid and reads abnormally high. The Ph could always be high anyway, but it could also be fine. Let the FC drift under 10 to know before you dose next time. 
This is entirely why we fix the PH as a SLAM prerequisite so that for the duration of the slam it should be ok while we can’t get an accurate reading.
This is entirely why we fix the PH as a SLAM prerequisite so that for the duration of the slam it should be ok while we can’t get an accurate reading.
Crud,.. I knew that,.. I’ve graduated from pool school multiple times! Guess I wasn’t thinking.With an FC of 10+ the PH test is invalid and reads abnormally high. The Ph could always be high anyway, but it could also be fine. Let the FC drift under 10 to know before you dose next time.
This is entirely why we fix the PH as a SLAM prerequisite so that for the duration of the slam it should be ok while we can’t get an accurate reading.
It’s ok. It takes a few rounds for all of it to click ‘together’ after you know all the individual stuffs.
cross one more off the list.
TexEdmond
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- Jun 16, 2021
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What's the orange reagent on the left? Is that the OTO yellow chlorine drops going off the charts?
TexEdmond
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- Jun 16, 2021
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Good news is with 60ppm Borates in the pool you've got a little bit of a safety net and won't be dropping your pH off quite so steep a cliff. Plus CSI not as big a factor with a vinyl liner. You'll probably be fine. Best way to bring pH back up and FC down? Have a pool party!
Crazy yellow is 10Ish. The next 10 are orange and the next 10 are brown. Give or take.
- Jul 21, 2013
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UV still there but sun angle has changed intensity of UV and we have shorter amount of daylight.
TexEdmond
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- Jun 16, 2021
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Dang. I noticed a little while back same thing happened with my pool. SWG went from 25% to 15% to 10% and I'm still not losing FC.
Exactly. As the season dwindles on you make too much FC, no matter where you are. An AWESOME problem with tons of leeway for error. In the spring it’s the exact opposite and you’re playing for real with little room for error. So be on the lookout next year for all the UV increase that need more FC production. Once the peak season hits it’s all gravy again for the back half.
The pool water is at 71, outside temp 75,.. might squeeze in another pool day this weekend,.. right now I’m running my robot.
- Sep 3, 2018
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I keep turning mind down too and the FC is not going down. I even wait a few days in between testing to let the sun burn some off but it's still high. Glad to see this is normal.
You are NOT alone.
If it gets particularly above target…….. notice I didn’t say ‘high’….. shut it off and let it drift down. But even THAT will take longer because of the lower daily loss.When you fire it back up, it will take some time to overproduce again, buying you several days. At some point the UV demand lines up with your production intervals and it’s just right again.
I’ve had mine completely off for 24 hours,.. FC is still above 12. My water is crystal clear!
- Sep 3, 2018
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Oh yeah. Guaranteed for both of you. I had the ‘clear’ cover which was really an opaque white and i saw half the FC loss when we used it. I imagine the blue one is even more.
- Sep 3, 2018
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Checked it again today and it’s still at 11.5. I turned it off and will check again in a couple of days.
BowserB
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- Jul 29, 2018
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Remember in winter the sun is actually lower--farther south (or farther north during southern hemisphere winter)--than it appears in the sky. The earth's atmosphere deflects the light, so it might look like the sun is 45 degrees from the horizon, but in fact it's lower and therefore travels farther through the ozone portion of the stratosphere, where UV is absorbed.
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