New pool and just converted to SWG, I think I am on the right track

[TexasEd]

• Just subscribed to the Pool Math App - You should see the link
• Have most of my levels in line with a few exceptions (see below)
• Set up my SWG at 50% with the pump flowing 24hrs and staying in between 4-6 ppm Free Chlorine
• Bought a FAS DPD test for chlorine
• Learned that 40# of salt raises my levels ~275 ppm and testing with a calibrated meter fluctuates between 3000 and 3200

Questions:

1. My CYA is about 25-30 all I have is test strips for that. What should I use for more precise tests or are the strips good enough. I don't want to over stabilize
2. If the pump is on above the flow rate for the SWG it does not matter how fast it goes, right? You don't get more chlorine generated at 2750 RPM than at 1000.
3. Do I need to SLAM or shock a pool that stays in that 4-6ppm FC range? Maybe just after heavy rain or parties?
4. If I raise my CYA will I have to adjust the current 50% output of my SWG to hit the right ratio of FC or will it stabilize?
5. What do I need to do to test Calcium Hardness? The test the PB gave me does not have one. I planned to use up that test kit and then get a K2005.

 

[mknauss]

What should I use for more precise tests or are the strips good enough. I don't want to over stabilize

Test Kits Compared TF100 or TFPro Salt from TFTestkits.net

You don't get more chlorine generated at 2750 RPM than at 1000.

You do not. As long as the flow switch is closed, the SWCG creates the same amount of chlorine regardless of pump RPM

Do I need to SLAM or shock a pool that stays in that 4-6ppm FC range?

No. If you know you will have a large FC consumption event, then add 5 ppm FC worth of liquid chlorine before it.

If I raise my CYA will I have to adjust the current 50% output of my SWG to hit the right ratio of FC or will it stabilize?

You might. Up to a reasonable level, a higher CYA will reduce FC loss per day.

What do I need to do to test Calcium Hardness? The test the PB gave me does not have one. I planned to use up that test kit and then get a K2005.

I suspect your fill water had calcium in it. You do need a test. Low CH can damage the plaster and high CH can cause scale.

 

[TexasEd]

Latest test results from Leslie Pools top, my test from 2 days ago on bottom. We had some tile repairs done Monday and they used some Acid to wash the patch, I don't know how much they added. I also broke down the filter and cleaned it for the first time since construction. A white mark on the bottom of the pool was something the plaster guy said was calcium buildup and that I probably had high Calcium Hardness. (The startup service company disagreed) The test today shows that I currently have low CH. I took a metal brush to those stains and they came up today but not previously. So I am guessing that the chemistry change due to several high rain events, plaster work and filter clean lowered my CH and now I am good.

I was not planning to add anything to raise CH since we have hard water, I just added salt and turned my autofill back on. Thoughts?

Edit: My salt was really measured at 2800 two days ago. I just forgot to enter it.
Edit 2: I'm working on dialing down the SWG. The 10 was at 50% production and the 7.5 was at 40%

 

[mknauss]

Can you post your own current test results, including CH?

Thank you.

 

[TexasEd]

Can you post your own current test results, including CH?

Thank you.

Apparently they do an adjusted TA number based on CYA and pH so I should not have used that number to calculate the CSI

 

[TexasEd]

ok, Just tested TA with a different (New) test kit and it came out to 90 and that is closer to the 80-100 that I see with test strips so I think I have a bad old kit. Is that possible?
The new test is a Taylor and turns Green to Red. The old one is OREQ (came from PB) and goes blue to yellow

This is with the revised TA number at 90

Edit: Did some reading and it sounds like high chlorine can cause strange effects. The Oreq test only tells me to use one drop of neutralizer and the Taylor had me use two. I'll try that next time I test with the Oreq.

 

[reggiehammond]

Do yourself a favor. Only test with a k2006c or tf100. Everything else is literal garbage and only serves to cause confusion and chemical mistakes. Delete the other stuff out of poolmath.

 

[TexasEd]

ok, two days in a row with the Taylor kit.



My pH and Chlorine are stable (cloudy days). If I look at this I think I need to add stabilizer to get into the 70-80 range. Then just monitor. I think my FC will come down when the clouds part. I have adjusted the generator down some since the 90+ degree days are gone.

I guess my next question is the CH. Most places say 200 is good but I think the recommendation here is 350.

 

[Msch99]

Which test kit are you using?

 

[TexasEd]

It is a Lesli's Total Poolcare DPD Test Kit 18-576 it is made by Taylor and has all Taylor reagents. It tests for everything the K2005 test has (Free & Total Chlorine or Bromide, pH, acid & Base Demand, TA, CH, CYA) Only difference I see is the box shape and the sample tube shape. I have a separate Taylor FAS-DPD kit. I have an electronic meter for Salt that I calibrated to 3000 ppm with a known sample.

 

[reggiehammond]

I wouldn't worry too much about CYA until late Spring; you don't need 70-80 at this time of year given the lack of UV and heat.

You'll lose CYA to rainfall and overflow as well.

 

[TexasEd]

What about the CH? This is a new pool we only put water in it July 28. Two and a half months ago. Should I raise it?

We have hard fill water from a limestone bottom lake so I’m surprised it is not higher but we have had a lot of rain and had it to the top of the coping a few times from rain.

 

[reggiehammond]

What about the CH? This is a new pool we only put water in it July 28. Two and a half months ago. Should I raise it?

We have hard fill water from a limestone bottom lake so I’m surprised it is not higher but we have had a lot of rain and had it to the top of the coping a few times from rain.

Watch your CSI - you could likely benefit from a small increase in CH. But I’d aim for the minimum as your fill water will push you higher each time you add water.