chlorine level question..lamotte <3ppm octo slide

djbordie

Member
Jul 19, 2019
8
toronto
Hey everyone, total newb here.

I recently purchased the lamotte pm51 kit.

My issue is that my new fill/swg/sand filter combo is showing high chlorine.

Decided to buy an intex 650gallon easy set, swcg and 10" sand filter setup to practice on before deciding if I can manage a larger semi in ground build myself.

Starting procedure:
- 3 hrs filter (after backwash new media)
- 16lb salt (as per calculator/ manual)
- 1hr setting of swcg
- 8hr boost (as per manual)
- 2.6oz cya (as per calculator. Only added 2oz) (sock method wih pre stirring in hot water)
-+2 hr filter after all that

Main issue is the FC is outside of the 3ppm max on the lamotte slide

Judging by a photo of the 10ppm slide I'm between 3 and 5 ppm.

Tried a "guess strip" and it looks like 5-10 ppm

Aside from buying the 10ppm lamotte slide which I will do next week....how does one tell the pool is safe and not over chlorinated?

Levels:
Fc - 3-5 lamotte or 5-10 guess strip
Salt - 2400
Cya - approx 20, not fully dissolved
Ph - 7.4
Alk- 100
Ch - 120

Sorry for the novel and hopefully my explanation of lamotte octo slide is sufficient.

Thank you for reading and opining,

My guess is let the sun do its work tomorrow and re test. But I want to swim tomorrow am with the fam. (Yes it's a tiny pool hah)
 

djbordie

Member
Jul 19, 2019
8
toronto
thank you, i have read them several times. not too informative though.

is the relationship cellular in that the more CYA, the more FC is safe? kind of like the cya grabs on to the free chlorine or something?

the other problem for me, was the CYA measurement with the Lamotte kit.

instructions were very very odd for CYA.

something about looking down a tube, which was inside of another tube. until the "black dot" started to disappear .
the only thing that happened to my black dot is it got muddier, maybe my CYA is 20, or even less. which was the minimum on the tester.

lets say I have zero CYA...is swimming in 10 FC bad?
given that we all would trust the Lamotte more, reading 3-5 NP in the manual.
However i only have the lamotte 0-3ppm slide.

111783
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
10,847
Northern NJ
You can mange your pool as a seasonal pool. See


Or you can follow


We generally do not see SWG on seasonal pools. But for a SWG we recommend CYA of 60-70.

With 0 CYA max safe CL is somewhere between 3 and 5 I think.

For a deeper dive into the FC and CYA relationship review

 
Last edited:

djbordie

Member
Jul 19, 2019
8
toronto
thank you, surely the CYA cant be zero.
the lamotte only tests to 20ppm minimum.
tomorrow is a new day of testing. the water is clean and clear. all values aside from FC and CYA are within range.
Dang my mind for having to ensure perfection in these scenarios.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
10,847
Northern NJ
You never get perfection in water chemistry. That is why all targets are stated as ranges. Anywhere in the range is ok.
 

jblizzle

Mod Squad
TFP Expert
LifeTime Supporter
May 19, 2010
43,260
Tucson, AZ
First, i think maintaining that tiny pool is going to be more difficult than a larger pool where there is more wiggle room.

Second, you really need a better test kit to get accurate FC readings. See Test Kits Compared although they likely cost more than your pool did.
 

setsailsoon

LifeTime Supporter
TFP Guide
Oct 25, 2015
1,607
Stuart/FL
is the relationship cellular in that the more CYA, the more FC is safe? kind of like the cya grabs on to the free chlorine or something?

the other problem for me, was the CYA measurement with the Lamotte kit.

instructions were very very odd for CYA.

something about looking down a tube, which was inside of another tube. until the "black dot" started to disappear .
the only thing that happened to my black dot is it got muddier, maybe my CYA is 20, or even less. which was the minimum on the tester.

lets say I have zero CYA...is swimming in 10 FC bad?
given that we all would trust the Lamotte more, reading 3-5 NP in the manual.
However i only have the lamotte 0-3ppm slide.
dj,

Lamotte make good kits and they've been around for a long time. Our experts have evaluated both and just recommend different kits than you have. I've used both brands and agree with TFP's experts the Taylor kits just work better for me personally. I'm sure both are accurate. The TF 100-xl has been very economical for me. I've had mine 5 years and replaced reagents twice (when they go on sale). CYA test is the hardest regardless of the brand. I think Lamotte's is needlessly more complicated. There are videos that can help just search on You-Tube. Also, you can buy a standard solution that is a known 50 ppm solution. You can test this to verify your technique is good. Eventually, you'll get the hang of it.

Don't really know if 10 ppm FC is a safe level below 20 ppm CYA. It's really not something I worry about since we always have more than 20 ppm for TFP pools. Maybe Jason would know? @jblizzle.

I hope this helps.

Chris
 

djbordie

Member
Jul 19, 2019
8
toronto
Fair enough. Thanks.
I will keep testing and see how this kits fares.

The cya has completely dissolved now and the sun is baking the pool. 81 degrees so far. I guess the real benefit of small pool size is quick warming!

Ideally the fc will go down shortly...

Or cya up.

We did just swim in it. Absolutely amazing so far. No red eyes or itchiness. Or dry skin. So maybe the fc is actually closer to 5ppm. Test time..
 

setsailsoon

LifeTime Supporter
TFP Guide
Oct 25, 2015
1,607
Stuart/FL
thanks, i assumed high chlorine was the culprite of skin issues. Dang the internet for having 1000 differing bits of info on any given topic...
Gotta watch out for that internet stuff... especially the ones that are selling something. But even if you ignore all of those there are those that are very passionate about almost anything. Me, I rely on solid, proven science that works. That's what I found here and what keeps me here.

Good luck to you and remember, anytime you need clarification or explanation experts are just a post away to help.

Chris