OK folks, long story here so bear with me. FYI, I am a trained chemist and have worked in industry and keep detailed records.
Been doing the TFP system for 3 yrs now with mostly spectacular results, minus one issue 2 years ago when on vacation and our substitute failed to follow my instructions for a week (lazy high school kid) and had some issues.
So, last year, pool was all good, except near year-end noted some increased chlorine consumption and found that our Jandy light (which has a well behind it w/o adequate circulation) had built up some algae. Opened, cleaned, cleared it.
On opening this year, pool was perfect. SLAM'd early in season. Had difficulty passing the OCLT....and guess what....it was the light well again. Cleaned and then passed 2 nights of OCLT with zero loss. Opened and pool was perfect all summer.
Numbers as follows....with this latest example from early August:
TC 5.5
FC 5.0
pH 7.6
CYA 35ish
CH 190
Borates 50ish
TA 210
These are pretty typical numbers for the past 3 yrs and i typically utilize b/w 2ppm and 5ppm of chlorine per day depending on the amount of sunlight the pool gets and the bather load. I do tend to keep my chlorine on the higher side as a safety precaution...my CYA was around 40 at year start....and had just gone down a bit from backwashing and water additions.
To the heart of the issue:
Beginning of August, I was out at the pool one evening and noted what i though was a little algae coming from behind the light fixture. Was using the hose at the time to add some water and used it to try and flush out the light well (rather than actually take it fully apart and clean it, which is a bit of a PITA). Next day had some mild haziness and just ran the chlorine level on the high side over the coming days, figuring it would clear pretty quickly.
But it didn't.
At no pont did my CC increase. It ran 0-0.5 throughout and i was maintaining FC level of 10+.
On 8/16 it took a drastic turn for the worse, becoming markedly cloudy without any obvious precipitating issue. The pH had dropped to 7.4 despite the added chlorine, and i noticed that chlorine demand was increasing. I tested my CYA on 8/19 and apparently gone....or certainly way less than 30.
Went to SLAM figuring things would clear quickly and I'd just re-add my CYA once the problem was over.
Well, still in problemsville. Since 8/19, I have been in SLAM. My lowest FC level since that date was 14.0. My chlorine demand has been through the roof. Typically i have been using 13ppm/24hrs. (This is roughly triple my normal consumption when on the high side). The CC have been between 0.5 and 1.0 the entire time. There's been no visible improvement in pool clarity. Still just a moderate cloudiness. Can barely see bottom in the 8ft end. I have been keeping the pool covered in the daylight (as i have no CYA, or little present...didn't want this to be eating my chlorine and increasing my already high usage). I have been opening in evenings and aerating with the water feature for several hours each evening. I opened the light well, cleaned completely and have just left the light out during this issue. I have also constructed a side port into the conduit going to the light well, so that in the future, i can add chlorine solution directly to the light well on a regular basis so that the stasis there, hopefully, will no longer build algae or whatever was in there. I have no visible algae anywhere. No discoloration...just the mild cloudiness. Have a robot cleaner i run every noght or every other to keep surfaces clean. backwashing weekly. Also, fyi, I use a 10% liquid pool shock as my chlorine source. I get it for $2/gallon at rural king and that raises me 4.3ppm. Also, despite the boatloads of chlorine i've added over the past 2 weeks while in SLAM, my pH has not budged. Has remained steady at 7.4. Which would suggest to me that there is still an ongoing issue. (Typically my pH slowly rises as you would expect with chlorine addition, requiring small amount of MA throughout the season to keep bringing it back down). Also, when i run my water feature, i get tiny white bubbles that surface to the pool in about 10-15 minutes (some seeming chemical reaction....wondering if this is somehow the elimination of nitrogen gas from the original CYA that's been broken down). there is a chloramine type odor to the pool as well. Today, i am at a FC of 17.5 and TC of 18.5.
This is a representative pic of the bubbling from a couple yrs ago when i had the same issue (tho the pool is cloudier now than at that time).
So, I have steadfastly stayed in SLAM assuming things would just get better, but haven't. Have had a month of cloudiness and no swimming for 2 weeks with a VERY surly wife and daughter.
Am going to try leaving the pool open all night to aerate more (having read that perhaps these CYA disappearance issues occur more in covered pools....which mine is a lot...and perhaps some anaerobic bacteria or reaction is to blame)...however, this makes me uncomfortable as we have no fence around the yard.
Have also toyed with the idea of a water dumping and addition. However, water here is incredibly expensive as we pay for both water and sewer and a 40% dump will cost around $400-$500 i believe. Conversely, my chlorine cost has been around $6/day.
Would welcome any advice/comments.
Thanks so much.
Been doing the TFP system for 3 yrs now with mostly spectacular results, minus one issue 2 years ago when on vacation and our substitute failed to follow my instructions for a week (lazy high school kid) and had some issues.
So, last year, pool was all good, except near year-end noted some increased chlorine consumption and found that our Jandy light (which has a well behind it w/o adequate circulation) had built up some algae. Opened, cleaned, cleared it.
On opening this year, pool was perfect. SLAM'd early in season. Had difficulty passing the OCLT....and guess what....it was the light well again. Cleaned and then passed 2 nights of OCLT with zero loss. Opened and pool was perfect all summer.
Numbers as follows....with this latest example from early August:
TC 5.5
FC 5.0
pH 7.6
CYA 35ish
CH 190
Borates 50ish
TA 210
These are pretty typical numbers for the past 3 yrs and i typically utilize b/w 2ppm and 5ppm of chlorine per day depending on the amount of sunlight the pool gets and the bather load. I do tend to keep my chlorine on the higher side as a safety precaution...my CYA was around 40 at year start....and had just gone down a bit from backwashing and water additions.
To the heart of the issue:
Beginning of August, I was out at the pool one evening and noted what i though was a little algae coming from behind the light fixture. Was using the hose at the time to add some water and used it to try and flush out the light well (rather than actually take it fully apart and clean it, which is a bit of a PITA). Next day had some mild haziness and just ran the chlorine level on the high side over the coming days, figuring it would clear pretty quickly.
But it didn't.
At no pont did my CC increase. It ran 0-0.5 throughout and i was maintaining FC level of 10+.
On 8/16 it took a drastic turn for the worse, becoming markedly cloudy without any obvious precipitating issue. The pH had dropped to 7.4 despite the added chlorine, and i noticed that chlorine demand was increasing. I tested my CYA on 8/19 and apparently gone....or certainly way less than 30.
Went to SLAM figuring things would clear quickly and I'd just re-add my CYA once the problem was over.
Well, still in problemsville. Since 8/19, I have been in SLAM. My lowest FC level since that date was 14.0. My chlorine demand has been through the roof. Typically i have been using 13ppm/24hrs. (This is roughly triple my normal consumption when on the high side). The CC have been between 0.5 and 1.0 the entire time. There's been no visible improvement in pool clarity. Still just a moderate cloudiness. Can barely see bottom in the 8ft end. I have been keeping the pool covered in the daylight (as i have no CYA, or little present...didn't want this to be eating my chlorine and increasing my already high usage). I have been opening in evenings and aerating with the water feature for several hours each evening. I opened the light well, cleaned completely and have just left the light out during this issue. I have also constructed a side port into the conduit going to the light well, so that in the future, i can add chlorine solution directly to the light well on a regular basis so that the stasis there, hopefully, will no longer build algae or whatever was in there. I have no visible algae anywhere. No discoloration...just the mild cloudiness. Have a robot cleaner i run every noght or every other to keep surfaces clean. backwashing weekly. Also, fyi, I use a 10% liquid pool shock as my chlorine source. I get it for $2/gallon at rural king and that raises me 4.3ppm. Also, despite the boatloads of chlorine i've added over the past 2 weeks while in SLAM, my pH has not budged. Has remained steady at 7.4. Which would suggest to me that there is still an ongoing issue. (Typically my pH slowly rises as you would expect with chlorine addition, requiring small amount of MA throughout the season to keep bringing it back down). Also, when i run my water feature, i get tiny white bubbles that surface to the pool in about 10-15 minutes (some seeming chemical reaction....wondering if this is somehow the elimination of nitrogen gas from the original CYA that's been broken down). there is a chloramine type odor to the pool as well. Today, i am at a FC of 17.5 and TC of 18.5.
This is a representative pic of the bubbling from a couple yrs ago when i had the same issue (tho the pool is cloudier now than at that time).
So, I have steadfastly stayed in SLAM assuming things would just get better, but haven't. Have had a month of cloudiness and no swimming for 2 weeks with a VERY surly wife and daughter.
Am going to try leaving the pool open all night to aerate more (having read that perhaps these CYA disappearance issues occur more in covered pools....which mine is a lot...and perhaps some anaerobic bacteria or reaction is to blame)...however, this makes me uncomfortable as we have no fence around the yard.
Have also toyed with the idea of a water dumping and addition. However, water here is incredibly expensive as we pay for both water and sewer and a 40% dump will cost around $400-$500 i believe. Conversely, my chlorine cost has been around $6/day.
Would welcome any advice/comments.
Thanks so much.
