CYA >200 - CL 33.5ppm

[Mattikuss]

I brought my TF-Pro test kit over to a friends who also has a pool in order to shame him about his inferior pool water quality. I ran some tests and, being a novice, didn't even know what to tell him about how messed up his levels seemed. Can someone explain to me how this happens? He has a chlorine pool and takes his water into the pool store every week. His FC was 33.5, CYA 200ish, and pH 7.6. I tried to test his CC but the DPD test was still pink after getting to 15ppm so I figured that the chlorine level and volume that I added from the reagent threw the test off (I know DPD tests are only accurate to 20ppm so I figured that had something to do with it). Regardless, how is this possible? Is this the norm for pool store victims? I know that CYA buffers Cl but can you have a balanced pool with levels this high? I was blown away.

 

[Newdude]

Did you do a diluted CYA test or guess that it was halfway to 100 when filling ? Either way its in the stratosphere.

They likely have him shock weekly as they do and it's been getting jacked over time.

 

[Mattikuss]

Did you do a diluted CYA test or guess that it was halfway to 100 when filling ? Either way its in the stratosphere.

They likely have him shock weekly as they do and it's been getting jacked over time.

It was halfway to 100.

So, is it safe to swim in? How does one fix this?

 

[Newdude]

It was halfway to 100.

Ooof. So you need to dilute the sample 50/50 with tap water, add R0013 as normal, squirt, squint, curse, then double the result.


If it is still 90+ diluted, go 2 parts tap and one part pool and triple it.

So, is it safe to swim in?

It needs to have an appropriate FC/CYA ratio, so we need to know the CYA. Min might be 20, or more. Envision this chart continuing and you'll get the idea.

 

[Endro32]

Using dichlor to shock regularly or trichlor tablets as a primary chlorine source will cause high CYA over time. Technically it can be safe to swim if the FC is high enough, but really the best thing would be to replace water until the CYA is back into a normal range. Then stick with bleach as the source of chlorine.

 

[Mattikuss]

Ooof. So you need to dilute the sample 50/50 with tap water, add R0013 as normal, squirt, squint, curse, then double the result.


If it is still 90+ diluted, go 2 parts tap and one part pool and triple it.

It needs to have an appropriate FC/CYA ratio, so we need to know the CYA. Min might be 20, or more. Envision this chart continuing and you'll get the idea.

View attachment 582491

What do the astrisk mean?

 

[Mattikuss]

Ooof. So you need to dilute the sample 50/50 with tap water, add R0013 as normal, squirt, squint, curse, then double the result.


If it is still 90+ diluted, go 2 parts tap and one part pool and triple it.

It needs to have an appropriate FC/CYA ratio, so we need to know the CYA. Min might be 20, or more. Envision this chart continuing and you'll get the idea.

View attachment 582491

Also, I noticed that pool math app has a much larger range than this charge for idea chlorine levels. For example: my CYA is 55 and I keep my Cl level at 4 according to pool math.

 

[Newdude]

What do the astrisk mean?

Not recommended for liquid chlorine pools. If it's trending upward of 90, it gives you some warning you should stop adding more cya (likely pucks or powdered shock)

Also, I noticed that pool math app has a much larger range than this charge for idea chlorine levels. For example: my CYA is 55 and I keep my Cl level at 4 according to pool math.

Pool math is just a calculator and reports minimum to high target. Minimum although not ideal is ok at the end of your FC swing but not ok before it happens each day.

Preferably you never sniff min at the end of the daily swing.

 

[Mattikuss]

Pool math is just a calculator and reports minimum to high target. Minimum although not ideal is ok at the end of your FC swing but not ok before it happens each day.

Preferably you never sniff min at the end of the daily swing.

Ooops. Okay, so do you try to stick to the high end? My range on pool math is actually 3-9, where should I aim for if I want my low swing to be 4? Does a higher Cl level within the range contribute to skin irritation like it does at hotels? I haven't run into a problem yet with how i've been doing it but I suppose that would only be inevitable if I continue.

 

[Newdude]

My range on pool math is actually 3-9, where should I aim for if I want my low swing to be 4?

Depends on the point in the season for one's climate. You could see 1 to 2 ppm loss early and late season and up to 4ppm loss mid season. (Warm climates have longer seasons but spring/summer/fall behaves similar for both). UV demand spikes and falls across the season like a bell curve.



Min FC
+ Recent daily loss
+ 1 or 2 ppm wiggle room
-------------------------------
= stoopid clear trouble free pool.

Does a higher Cl level within the range contribute to skin irritation like it does at hotels?

Looooooool. Absolutely not. Hotel pools are their own animal, and likely mismanaged. Thinking back, almost every pool I was ever in was gross. The chlorine smell and feel comes from mismanagement. We don't have those issues here.

Long story short, my tap water is harsh and often smells like chlorine with 1 or 2 FC and no CYA. My pool up to SLAM level for my CYA is not. We've swam there, or halfway there many times and never once compared to my plain old tap water.

 

[Mattikuss]

Depends on the point in the season for one's climate. You could see 1 to 2 ppm loss early and late season and up to 4ppm loss mid season. (Warm climates have longer seasons but spring/summer/fall behaves similar for both). UV demand spikes and falls across the season like a bell curve.

View attachment 583580

Min FC
+ Recent daily loss
+ 1 or 2 ppm wiggle room
-------------------------------
= stoopid clear trouble free pool.



Looooooool. Absolutely not. Hotel pools are their own animal, and likely mismanaged. Thinking back, almost every pool I was ever in was gross. The chlorine smell and feel comes from mismanagement. We don't have those issues here.

Long story short, my tap water is harsh and often smells like chlorine with 1 or 2 FC and no CYA. My pool up to SLAM level for my CYA is not. We've swam there, or halfway there many times and never once compared to my plain old tap water.

I don't think I could live without you, NewDude. You helped me build and design my pool, pick my equipment, and you regularly answer my questions with patience and easy to understand answers. Thank you.