CH Testing - What is Blue?

[Sunnydaze]

Moved from here.

Keep going until you get to the light baby blue. That's the final CH number.

Not to hjjack but I've seen this advice before but my CH test never turns baby blue. It remains a light purple color. I can add 15 extra drops after the water turns light purple and it will not change the color any further. Why would that be?

 

[mknauss]

Why would that be?

Very high CH levels.
The transition can be effected by metals in your water. Do the metal interference process described in the Testing Directions in Pool School.

 

[Sunnydaze]

Very high CH levels.
The transition can be effected by metals in your water. Do the metal interference process described in the Testing Directions in Pool School.

It happens on my tap water test too. Maybe its just my interpretation of light purple vs baby blue because the color does not further change from the initial change which would normally indicate the end of the test. The tap water gives me a reading of 250 hardness which is about right for my city water. My pool was just filled in November and it tests at 325 now.

 

[mknauss]

Maybe its just my interpretation of light purple vs baby blue because the color does not further change from the initial change which would normally indicate the end of the test. T

SmartStir really helps with this test. My CH test is purple but has a distinct transition to baby blue. The light on the SmartStir helps see it.

 

[Sunnydaze]

SmartStir really helps with this test. My CH test is purple but has a distinct transition to baby blue. The light on the SmartStir helps see it.

I use a smart stir as well. Here, i made a video if you wouldn't mind watching it to give me your opinion on what I'm seeing for the color change. At drop 10, it turns to what I'm calling more of a light purple. I added extra drops with no change. Is that what you consider baby blue and the end point? We could move this to a new thread, if needed. dont wanna hijack this one. I'm really questioning the accuracy of my ch testing now. This is a test of my tap water:

Thanks

 

[mknauss]

It changes to baby blue at 10 drops.
You can use an extra drop of R0011L to make the colors more enhanced.
I do suggest doing the metals interference process as stated in the Testing Directions. At least 5 drops of R0012 to start.

 

[Sunnydaze]

It changes to baby blue at 10 drops.
You can use an extra drop of R0011L to make the colors more enhanced.
I do suggest doing the metals interference process as stated in the Testing Directions. At least 5 drops of R0012 to start.

Great, thank you. I guess i was being too specific on the color change because i get the same color on my pool water sample as well. I'll try the metal interference process but I'm pretty confident in the numbers I've gotten now knowing what the color should be.

 

[proavia]

@Kevinr14 - Maybe Marty @mknauss will be kind enough to split posts related to your post into its own thread to better help you out.

The video does show a change to a bluish hue. I am in Chandler as well, and I see a similar change of color - although a bit more bluish.

If you are confident in your CH number, let your pH drift up to the upper 7's to get your CSI in range.
Shoot for a CSI of 0.0 to -0.30
As your CH level rise due to evaporation, you can use a lower pH to keep CSI in range. You can manage your CSI up to about a CH of 1000-1200 if you carefully manage your pH and TA - then you are going to need to drain and refill. You will probably evaporate your entire pool volume (or more) ofer the course of a year in our desert climate. If you have a water softener, consider plumbing it into your autofill.

 

[KJB1]

It happens on my tap water test too. Maybe its just my interpretation of light purple vs baby blue because the color does not further change from the initial change which would normally indicate the end of the test. The tap water gives me a reading of 250 hardness which is about right for my city water. My pool was just filled in November and it tests at 325 now.

I think it is your definition of “blue” and mine too. I have the same problem and used a bunch of reagent just to see the colors. Did the metal interference test too and still got a purpleish blue color even with like 10 extra drops. You won’t get a deep blue. Also YouTube some videos of guys testing, they get the purpleish blue color. I was hoping for that 10,000 flushes additive toilet blue

 

[Sunnydaze]

@Kevinr14 - Maybe Marty @mknauss will be kind enough to split posts related to your post into its own thread to better help you out.

The video does show a change to a bluish hue. I am in Chandler as well, and I see a similar change of color - although a bit more bluish.

If you are confident in your CH number, let your pH drift up to the upper 7's to get your CSI in range.
Shoot for a CSI of 0.0 to -0.30
As your CH level rise due to evaporation, you can use a lower pH to keep CSI in range. You can manage your CSI up to about a CH of 1000-1200 if you carefully manage your pH and TA - then you are going to need to drain and refill. You will probably evaporate your entire pool volume (or more) ofer the course of a year in our desert climate. If you have a water softener, consider plumbing it into your autofill.

Thank you. Yeah, I've been watching the csi too and seeing how different parameters affect it. Right now, its .08. When my ph hits 8, I've been lowering to 7.6.

 

[proavia]

Marty's suggestion to use an extra drop of the R011L reagent to intensify the color will also help.

It's all about tweaking the chemistry levels to keep CSI in range. You can also let your TA decrease to 60-ish to help out. No need to force it down, normal acid additions will s-l-o-w-l-y lower it. Given our fill water TA of 120-140, it may take a while. None of this needs to be rocket science - play around with numbers in PoolMath to see what changes actually do to CSI.

 

[Sunnydaze]

Marty's suggestion to use an extra drop of the R011L reagent to intensify the color will also help.

It's all about tweaking the chemistry levels to keep CSI in range. You can also let your TA decrease to 60-ish to help out. No need to force it down, normal acid additions will s-l-o-w-l-y lower it. Given our fill water TA of 120-140, it may take a while. None of this needs to be rocket science - play around with numbers in PoolMath to see what changes actually do to CSI.

After joining here, i got some advice and brought my TA down to 70. It definitely helped with my ph rise. I figure it will also help when my CH gets higher throughout summer.

I wish I had a water softener but don't. This hard AZ water is brutal on everything!

 

[proavia]

On an up note - City of Chandler water is presently pretty cheap. A full drain/refill on my 12,300 gallon pool added about $30 to my bill. I was doing a drain/refill about every 3 years or so - usually in spring and when the CH got to the 1200-1500 range. Drain/refill was cheaper then the additional MA I needed to keep the pH at 7.2 - . I now have my softener plumbed to my autofill, so will see how that goes.

 

[Sunnydaze]

On an up note - City of Chandler water is presently pretty cheap. A full drain/refill on my 12,300 gallon pool added about $30 to my bill. I was doing a drain/refill about every 3 years or so - usually in spring and when the CH got to the 1200-1500 range. Drain/refill was cheaper then the additional MA I needed to keep the pH at 7.2 - . I now have my softener plumbed to my autofill, so will see how that goes.

Maybe one day, I'll get a water softener. I saw Marty's that he installed outdoors just for his pool. That might be in my future. I've already spent too much money on this pool lol.

Regarding draining the pool here in Chandler/phoenix area...i assume it's safe to completely drain given our water table is not likely to be anywhere near the surface? Any other concerns in completely draining? I know it shouldn't be done in hot weather. I have a plaster pool. It was just filled in November so hopefully i can go 3 years like you have.

 

[proavia]

Given our lack of rain, I haven't had any issues draining my pool. When I need to drain, I usually do it in February or March before it gets too hot. And I hose the walls down during drain and refill to help keep them moist. The more hoses you can use to fill, the faster it will go.