Youfah Mizzum

Well-known member
Sep 7, 2020
61
Sydney Australia
Pool Size
22000
Surface
Plaster
Chlorine
Salt Water Generator
I've had my pool about 5 years and everything has been humming along nicely. A few incidences over the years which TFP forums have assisted immensely.

Anyway, this summer (I'm in Australia) I've had a minor issue. Despite my SWG being on a very low setting (it's now on 5%, the lowest setting) I still have free chlorine testing around the 10 to 12 ppm mark. Using the ClearChoiceLabs test kit.
I think as a result of the consistently high free chlorine, my Ph levels are always hovering on the higher alkaline side, each week I test and its typically above 8 so I am consuming acid more than I have previously.

One advantage of the high chlorine is my pool has consistently been crystal clear all summer! Wonderful, and allows me to not be too concerned about an excess of leaf litter if I don't get to vacuum each week. I can leave it for 3 weeks and not be concerned.

I keep my pool covered so CYA is not massively critical and anyway because I have high Ch, it's not like I need CYA to keep the chlorine from dissipating - there is sufficient coming in from my SWG chlorinator.

I'm just wondering what might be the cause? I think I heard somewhere that aerating the return water (or a fountain/water feature) can cause an increase in chlorine and/or Ph? I've tried to find a reference for that on TFP but couldn't find it so maybe that's rubbish? Anyway...I don't have a water feature or fountain. I have 2 return eyes. One is pointed down towards the pool floor, the other more horizontal, slightly upwards and creates some surface movement. If indeed aeration can increase chlorine, maybe that's it?

Ideally I'd like to have the free chlorine about the 3 to 5 ppm range.
 
I've had my pool about 5 years and everything has been humming along nicely. A few incidences over the years which TFP forums have assisted immensely.

Anyway, this summer (I'm in Australia) I've had a minor issue. Despite my SWG being on a very low setting (it's now on 5%, the lowest setting) I still have free chlorine testing around the 10 to 12 ppm mark. Using the ClearChoiceLabs test kit.
I think as a result of the consistently high free chlorine, my Ph levels are always hovering on the higher alkaline side, each week I test and its typically above 8 so I am consuming acid more than I have previously.

One advantage of the high chlorine is my pool has consistently been crystal clear all summer! Wonderful, and allows me to not be too concerned about an excess of leaf litter if I don't get to vacuum each week. I can leave it for 3 weeks and not be concerned.

I keep my pool covered so CYA is not massively critical and anyway because I have high Ch, it's not like I need CYA to keep the chlorine from dissipating - there is sufficient coming in from my SWG chlorinator.

I'm just wondering what might be the cause? I think I heard somewhere that aerating the return water (or a fountain/water feature) can cause an increase in chlorine and/or Ph? I've tried to find a reference for that on TFP but couldn't find it so maybe that's rubbish? Anyway...I don't have a water feature or fountain. I have 2 return eyes. One is pointed down towards the pool floor, the other more horizontal, slightly upwards and creates some surface movement. If indeed aeration can increase chlorine, maybe that's it?

Ideally I'd like to have the free chlorine about the 3 to 5 ppm range.
The chlorine is not affected by water aeration. You just need to turn off the SWCG so it stops making chlorine. But note that you do need to manage the CYA because it buffers the harshness of chlorine and will help prevent bleaching of surfaces. Just because the pool is covered doesn’t mean you can ignore CYA. Your cover can be damaged by the unbuffered chlorine as well.

Always…always follow the CYA/FC chart.
 
*Also note that the phenol red ph test is inaccurate at fc levels above 10ppm.
It often reads higher than reality. This can result in over dosing with too much acid.
Turn off the swcg or leave the pool uncovered to allow fc to fall below 10ppm & then check & adjust ph if needed.
 
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One advantage of the high chlorine is my pool has consistently been crystal clear all summer! Wonderful, and allows me to not be too concerned about an excess of leaf litter if I don't get to vacuum each week. I can leave it for 3 weeks and not be concerned.
We call it #teamrunhot. And belated Welcome to the club. :)

Huge storm coming ? Meh. 🤷‍♂️ We're covered
High UV day ? Meh. 🤷‍♂️ We're covered.
Busy elsewhere ? Meh. 🤷‍♂️ We're covered.

Maintain a 30 CYA for bather comfort and for your surfaces/equipment as said above.
 
Tested everything 1 hour ago;
FC: 5.5
CYA: 40
Ph. 8.0. ClearChoiceLab kits says 7.2
TA. 40. ClearchoiceLab kit says 30
CH 375

You've left out how TA plays into the PH of the pool.
Fair point. I hadn't tested TA for a few months. My bad - but in my defense its because it has always been steady around the 70-80 mark.
I tested just now & lo & behold it is quite low, around the 30 to 40 mark. I have two test kits and one says 30, the other says 40. Either way it's low so I've added some bicarb.

*Also note that the phenol red ph test is inaccurate at fc levels above 10ppm.
It often reads higher than reality. This can result in over dosing with too much acid.
I find my expensive kit from ClearChoiceLabs is quite difficult to get a colour (the correct spelling :D) reading from the vial so I use the phenol red test as it's just easier to determine a colour variance between the Ph levels.
Anyway just now the phenol red test was reporting arounf the 8.0 mark. The CCL kit I decided to compare and it was reading around the 7.2.
This correlates to your comment which I was otherwise unaware of. So yeah - I was possibly overdosing the acid.

Thanks to the replies. Now that I've added some bicarb I'll let that mix in for a few days and retest on the weekend (Wednesday today).

Huge storm coming ? Meh. 🤷‍♂️ We're covered
High UV day ? Meh. 🤷‍♂️ We're covered.
Busy elsewhere ? Meh. 🤷‍♂️ We're covered.
Fair sentiments, running hot just allows that leeway. I know when I tried to maintain FC around the 2 to 4, if I wasn't on the ball and constantly monitoring then a storm would turn my pool green (slightly) and I'd be doing a SLAM. Running just a 1 or 2 ppm above gives me a bit of comfort.
 
Tested everything 1 hour ago;
FC: 5.5
CYA: 40

I find my expensive kit from ClearChoiceLabs is quite difficult to get a colour (the correct spelling :D) reading from the vial so I use the phenol red test as it's just easier to determine a colour variance between the Ph levels.
+ 1 on #teamrunhot

My neighbor has one of the ClearChouceLabs and it is difficult to recognize the color especially when it gets to be above 70 degrees even with lots of practice. I like my TFP Pro as I feel like it is a bit more organized especially when I keep in in my 10 sqft. aluminum container. :D
 
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