You're this far along - if it were me I would bring it up to SLAM level again. Worst case you've spent a couple bucks on chlorine and best case you ended the war!
Help with readings...clear water...low FC...0 CC
- Thread starter Randrx2
- Start date
- Dec 13, 2018
- 436
- Pool Size
- 30000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
FC=25ppm at about 5:00PM and still at 25ppm at 8:45PM. Wishing for a good overnight test!
- Dec 13, 2018
- 436
- Pool Size
- 30000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
FC=23ppm this morning. Down 2ppm. Darn!
The sample at 25ppm last night was done with a 5ml sample at 1ppm per drop. Same test for this mornings 23ppm sample. I am guessing there is a margin of error there? I should have done the more accurate 10ml sample last night to get within a 0.5ppm margin of error.
I am plan to let it ride through the day today and do some swimming and keep the levels up above 24ppm with the SWG. I'll try another more accurate overnight test tonight.
Pool water is very clear! No haze, no floaties!
The sample at 25ppm last night was done with a 5ml sample at 1ppm per drop. Same test for this mornings 23ppm sample. I am guessing there is a margin of error there? I should have done the more accurate 10ml sample last night to get within a 0.5ppm margin of error.
I am plan to let it ride through the day today and do some swimming and keep the levels up above 24ppm with the SWG. I'll try another more accurate overnight test tonight.
Pool water is very clear! No haze, no floaties!
- Dec 13, 2018
- 436
- Pool Size
- 30000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
SUCCESS! (I believe)
So starting at FC=23ppm yesterday morning, I ran the SWG for a few hours. The FC got to 25ppm. I turned off the SWG. We had a sunny day and did some swimming and got "some" rain (about 2-3" rise in water level). I tested last night and was at 22ppm. That number seemed in line with what I should suspect considering sun and swimmer burnout and dilution due to rain. This morning, FC=21.5ppm. CC=0.5ppm (barely pink and 1 drop cleared it). Water is clear, less than 1ppm FC loss, and CC less than 0.5.
Thank you all for help and for this site! Looking forward to paying it forward!
So starting at FC=23ppm yesterday morning, I ran the SWG for a few hours. The FC got to 25ppm. I turned off the SWG. We had a sunny day and did some swimming and got "some" rain (about 2-3" rise in water level). I tested last night and was at 22ppm. That number seemed in line with what I should suspect considering sun and swimmer burnout and dilution due to rain. This morning, FC=21.5ppm. CC=0.5ppm (barely pink and 1 drop cleared it). Water is clear, less than 1ppm FC loss, and CC less than 0.5.
Thank you all for help and for this site! Looking forward to paying it forward!
Attachments
Oly
Gold Supporter
Less than five days to get the algae out of your pool water. 
Catching the signs of a bio contamination early and then
a no nonsense aproach of a SLAM did the job, well done.
Now to enjoy your success.
Catching the signs of a bio contamination early and then
a no nonsense aproach of a SLAM did the job, well done.
Now to enjoy your success.
- Dec 13, 2018
- 436
- Pool Size
- 30000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
So how did this happen...
I am new to pool ownership and had some knowledge, but not nearly enough. I was testing diligently, but not really understanding the numbers. I was focused on keeping pH down per the pool installer for the finish.
I always thought 2-3 ppm FC was good because I had heard that SWG pools could operate at a lower chlorine levels. I had no understanding of the Chlorine/CYA interaction. Once my FC numbers were coming up to 5 ppm, I thought that is too high, I need to back off the SWG percentage. Looking back at my CYA numbers, I should have been targeting 4-5 ppm FC. Also, I did not realize I was losing that much chlorine due to the sun.
I think that over time, the algae was building up, but not turning green. I was possibly on the edge, so to say. Once I saw the cloudy water and had cranked up the SWG to 100%, it was too late. The chlorine being produced was just being eaten up and I was still on that edge of pool turning green.
Is this a correct assessment? Would love to hear some opinions.
Thanks.
P.S. I think that the beginning of the SLAM process is the most critical. I did not have an algae problem turning pool green, pool wasn't that cloudy, and CC was less than 0.5 ppm. If I could have kept the pool at SLAM level that first night and been able to test every hour for say the first 6 hours, I think that would have gotten to a successful OCLT sooner.
I am new to pool ownership and had some knowledge, but not nearly enough. I was testing diligently, but not really understanding the numbers. I was focused on keeping pH down per the pool installer for the finish.
I always thought 2-3 ppm FC was good because I had heard that SWG pools could operate at a lower chlorine levels. I had no understanding of the Chlorine/CYA interaction. Once my FC numbers were coming up to 5 ppm, I thought that is too high, I need to back off the SWG percentage. Looking back at my CYA numbers, I should have been targeting 4-5 ppm FC. Also, I did not realize I was losing that much chlorine due to the sun.
I think that over time, the algae was building up, but not turning green. I was possibly on the edge, so to say. Once I saw the cloudy water and had cranked up the SWG to 100%, it was too late. The chlorine being produced was just being eaten up and I was still on that edge of pool turning green.
Is this a correct assessment? Would love to hear some opinions.
Thanks.
P.S. I think that the beginning of the SLAM process is the most critical. I did not have an algae problem turning pool green, pool wasn't that cloudy, and CC was less than 0.5 ppm. If I could have kept the pool at SLAM level that first night and been able to test every hour for say the first 6 hours, I think that would have gotten to a successful OCLT sooner.
Oly
Gold Supporter
- Dec 13, 2018
- 436
- Pool Size
- 30000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
A week later and things are looking good.
I haven’t had to add chlorine or run SWG for awhile. Waiting for levels to come down. Not losing much FC. Surprising given the heat and sun. FC is around 8.5 to 9.5. Trying to dial in the SWG to get it to about 7.
I slowly brought CYA up to 70-80. BTW, I hate this test! I wish there was a titration test for this. I started to just fill the vial to 100, then look, then 90 then look, etc. I think I get a reflection of my head in the vial and that is the “dot” I see. The fill and look method seems to be better. I can’t believe it took me this long to figure out.
We stopped our son’s swim lessons at the public pool. No more burning itchy eyes!
I saw some other posts about being a TFP “pool snob” and am glad there are others out there. I think I am turning into one. I cannot look at another pool now without thinking “I wonder what the CUA/Chlorine relationship level is?”
Thank you all for the wealth of info!!!
I haven’t had to add chlorine or run SWG for awhile. Waiting for levels to come down. Not losing much FC. Surprising given the heat and sun. FC is around 8.5 to 9.5. Trying to dial in the SWG to get it to about 7.
I slowly brought CYA up to 70-80. BTW, I hate this test! I wish there was a titration test for this. I started to just fill the vial to 100, then look, then 90 then look, etc. I think I get a reflection of my head in the vial and that is the “dot” I see. The fill and look method seems to be better. I can’t believe it took me this long to figure out.
We stopped our son’s swim lessons at the public pool. No more burning itchy eyes!
I saw some other posts about being a TFP “pool snob” and am glad there are others out there. I think I am turning into one. I cannot look at another pool now without thinking “I wonder what the CUA/Chlorine relationship level is?”
Thank you all for the wealth of info!!!