Firstly some background information:
Location: Sydney, Australia (well, just an hour north near Gosford)
Pool volume: 22,000 L (4850 gallons)
Salt water chlorinator
Pool cover mostly kept on except when swimming
No opening/closing routine for winter/summer. Coldest it gets here is around 5 deg C (40 deg F)
Age of pool: 2 years, so pretty new.
Surface: plaster - beadcrete.
Chem test kit from Clear Choice Labs (very similar to Taylor I believe). I also take a sample to my local pool shop.
I don't know which forum to post this in as it falls under multiple headings, but I figure Water Chemistry might be the most appropriate.
So onto the query!
Last November we had a big windstorm which deposited a fair bit of leaves and debris (dust, twigs etc) into the pool.
I hadn't tested or checked the water for about a week (it's under my pool cover) but when I uncovered the water, it was a bit green & chlorine level was basically 0 as expected with all that Crud!
So I increased the chlorinator level & added extra liquid chlorine to clear up the outbreak. I basically SLAMmed with a big dose of liquid chlorine for a few days.
Vacuumed, backwashed a few times.
A few days later & we're all good. Nice clear water.
I mention the above as that seemed to be the start of my issues - whether it has any bearing or not I don't know, maybe just coincidence.
But I was never able to keep the chlorine level at appropriate levels, around the 4 to 5 ppm.
Since I have had the pool, my chlorinator would run for about 9 to 10 hours a day split between day and night, so 5 hours in the day and 4 hours at night. And it's chlorination level was about 35%. That is summertime. In the winter, it's about 7 hours at 5%.
But since the November incident I cannot get a chlorine reading above 1 (usually 0 to 0.5) & I have increased the running to 11 hours a day, running at 95%.
I just don't know what is causing the low levels - either something is consuming the chlorine e.g. algae. Or the chlorinator isn't producing chlorine to it's pre November levels. By the way, I can visually see the chlorine getting produced by the cell blades so I know it IS working.
All other chem levels (CYA, salt, TA, CH, phosphates et al) are well within correct ranges although I have always found it hard to maintain the recommended CYA level (70 to 80) so the CYA is typically around 50 but it drops quickly so each week I find I need to add more CYA to keep it at the 50 mark or thereabouts. That has always been the case but just mentioning it in case it has any relevance.
I did have low salt thanks to flooding rains over 2022 but I have since thrown in a few bags of salt so all good there. It's currently sitting around 5000 ppm.
I vacuum every 4 to 5 days using a robot (this one Dolphin S 200)
Over the following weeks, I have kept a close eye on chem levels, and have added liquid chlorine just to boost the chlorine level.
Nevertheless, just before Xmas I submitted a warranty claim on the chlorinator as I had eliminated just about every other option.
Last Friday (today is Tuesday) the technician came out and replaced the chlorinator with a new controller and cell, so the whole kit was replaced with new (or what I assume is new).
So it's 4 days later & was hoping to see chlorine levels back up to 5 ppm or even higher as it's running 11 hours a day at 95%.
But alas, the chlorine levels are still in the small 0.nn range.
I am completely baffled why I can't get good chlorine levels.
Location: Sydney, Australia (well, just an hour north near Gosford)
Pool volume: 22,000 L (4850 gallons)
Salt water chlorinator
Pool cover mostly kept on except when swimming
No opening/closing routine for winter/summer. Coldest it gets here is around 5 deg C (40 deg F)
Age of pool: 2 years, so pretty new.
Surface: plaster - beadcrete.
Chem test kit from Clear Choice Labs (very similar to Taylor I believe). I also take a sample to my local pool shop.
I don't know which forum to post this in as it falls under multiple headings, but I figure Water Chemistry might be the most appropriate.
So onto the query!
Last November we had a big windstorm which deposited a fair bit of leaves and debris (dust, twigs etc) into the pool.
I hadn't tested or checked the water for about a week (it's under my pool cover) but when I uncovered the water, it was a bit green & chlorine level was basically 0 as expected with all that Crud!
So I increased the chlorinator level & added extra liquid chlorine to clear up the outbreak. I basically SLAMmed with a big dose of liquid chlorine for a few days.
Vacuumed, backwashed a few times.
A few days later & we're all good. Nice clear water.
I mention the above as that seemed to be the start of my issues - whether it has any bearing or not I don't know, maybe just coincidence.
But I was never able to keep the chlorine level at appropriate levels, around the 4 to 5 ppm.
Since I have had the pool, my chlorinator would run for about 9 to 10 hours a day split between day and night, so 5 hours in the day and 4 hours at night. And it's chlorination level was about 35%. That is summertime. In the winter, it's about 7 hours at 5%.
But since the November incident I cannot get a chlorine reading above 1 (usually 0 to 0.5) & I have increased the running to 11 hours a day, running at 95%.
I just don't know what is causing the low levels - either something is consuming the chlorine e.g. algae. Or the chlorinator isn't producing chlorine to it's pre November levels. By the way, I can visually see the chlorine getting produced by the cell blades so I know it IS working.
All other chem levels (CYA, salt, TA, CH, phosphates et al) are well within correct ranges although I have always found it hard to maintain the recommended CYA level (70 to 80) so the CYA is typically around 50 but it drops quickly so each week I find I need to add more CYA to keep it at the 50 mark or thereabouts. That has always been the case but just mentioning it in case it has any relevance.
I did have low salt thanks to flooding rains over 2022 but I have since thrown in a few bags of salt so all good there. It's currently sitting around 5000 ppm.
I vacuum every 4 to 5 days using a robot (this one Dolphin S 200)
Over the following weeks, I have kept a close eye on chem levels, and have added liquid chlorine just to boost the chlorine level.
Nevertheless, just before Xmas I submitted a warranty claim on the chlorinator as I had eliminated just about every other option.
Last Friday (today is Tuesday) the technician came out and replaced the chlorinator with a new controller and cell, so the whole kit was replaced with new (or what I assume is new).
So it's 4 days later & was hoping to see chlorine levels back up to 5 ppm or even higher as it's running 11 hours a day at 95%.
But alas, the chlorine levels are still in the small 0.nn range.
I am completely baffled why I can't get good chlorine levels.
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