Question re: FC Usage in Green Pool

[wkener2]

Yes Ma'am I've been vacuuming twice a day for the last 48 hours and backwashing the filter once the pressure goes up 25% from clean pressure. Also adding a little DE to the filter after every backwash and a sock in the skimmer. I agree with everything that has been said on this thread, and if I wasn't up against a "deadline" I definitely prefer the 100% BBB method I do believe that the debris in the pool played a factor in how long it took to clean up, but I still cannot account for the almost total lack of FC demand this year Anyway, who am I to complain? I saved a lot if $$ on bleach!

 

[Azgirl71]

I agree that the debris played a big factor on the progress. I know once I got all the pine needles ect out of the bottom it moved much quicker for me.

 

[wkener2]

Yes, but what was your chlorine demand like? I've never shocked a green pool like this that didn't use up chlorine like it was on a bender!

 

[Azgirl71]

There is a link to my slam in my signature. My entire slam is there. My demand was pretty high until I got the debris out. Then it slowed some. I chose to bring my FC above shock levels so I knew I would always at least be at or above shock level once my numbers were holding better.

 

[wkener2]

Yeah, that is what it normally is like for me when I open... huge demand up front then dropping significantly once everything in the water was dead. I never had that demand this year...

 

[Azgirl71]

Who knows.

 

[wkener2]

All,

Well, we had our party on Saturday and we had people in the pool all day! I want to share this pic from this morning, and thank all of you for your encouragement and assistance. TFP is a fantastic resource!:

 

[Azgirl71]

Congrats on a job well done

 

[wkener2]

Testing results from this morning:

FC 10.5
CC 0
CYA 50
PH 7.2

I will raise PH a little and let the FC drop down to 6-7 and maintain, but I'm looking pretty good!

 

[Azgirl71]

Ph won't be correct with FC over 10. Let FC drop some and retest it. What is your TA? PH should rise naturally with aeration.

 

[wkener2]

I have not tested TA... I let the FC drop to 5ppm and tested PH again this morning. PH was 7.2-7.3, so I added 76oz of 20 Mule Team which should get me to around 7.5-7.6. Pool is sparkling now

 

[mamabear020305]

OP,

I just wanted to say that I am so glad I found your post this season. I have used the BBB/SLAM method successfully for the past 4 years but this year, my pool was making no progress at all. And the FC was not being consumed like it has done every other time. It was mind boggling AND frustrating to say the least. I almost started to think that my pool had some crazy type of algae that was resistant to chlorine because, despite keeping the FC at mustard shock levels for almost a week, I was seeing little to no progress yet the FC was not declining significantly.

After reading your thread many, many times, I took the leap and added floc to the pool yesterday (following the directions on the bottle and letting it sit overnight) and noticed large amounts of yellowish stuff all over the bottom of the pool when I got home this afternoon, so I vacuumed it all to waste. I can't even begin to describe the difference a day made! It is no longer green and is cloudy blue/teal. I am going to keep the FC levels high until I know I am finished SLAMing and every last particle of algae is DEAD.
Thanks so much for sharing your experience and pics!

 

[chem geek]

Clarifiers and flocculants work at times and not at others since technically you need to dose them in amounts relevant to exactly the kind and sizes of particles in the pool. For particles that can get filtered out or that can get partially oxidized by chlorine and coagulated, then chlorine and filtration works. When the particles are too small to be filtered, as is more often the case with sand filters, then all the chlorine and filtration in the world isn't going to help (though DE added to the sand filter will usually help).