Please help me troubleshoot spa issue

[ak.operator]

I'm having trouble with my spa that I need corrected. It's a 600 gallon spa and I'm using the Taylor K-2006C testing kit. My test results came after we changed the filters, drained, filled, and balanced the spa TWICE (heavy weekend usage with no chlorine in spa)! First attempt of balancing spa we got weird readings that we weren't use to same went with the second attempt.


Here are my results:

Chlorine (Free, Combined) Test

Test unit calls for 25 mL of sample water with 2 dippers of R-0870 until sample turns pink. If pink color disappears, add R-0870 until sample water turns pink.

*Followed instructions and pink color disappeared so added 2 more dippers of R-0870 until sample turned pink.

Test unit calls to add R-0871 reagent drops until pink sample water turns clear then multiplying drops by .2 ppm to find out free chlorine levels.

*Followed instructions and ended up having to add 100 drops of reagent. 10 ppm free chlorine.


pH Test

Test unit calls for 44 mL of sample water with 5 drops of R-0004 then to invert to mix

*Followed instructions and sample water turned purple. I have no idea what that means!?!


Total Akalinity Test

Test unit calls for 25 mL of sample water with 2 drops of R-0007, 5 drops of R-0008 until water turns green, then add R-0009 until sample water turns from green to red. Multiply drops of R-0009 by 10 to find out total alkalinity.

*Followed instructions and sample water turned a light hint of green. Added R-0009 to see if I could get a color change. After 4 drops it changed from a light hint of green to a light hint of red. I'm use to seeing an obvious green color change but not here.


Calcium Hardness Test

Test unit calls for 25 mL of sample water with 20 drops of R-0010, 5 drops of R-001L until water turn red if calcium is present, then add R-0012 until sample water turns from red to blue. Multiply drops of R-0012 by 10 to find out calcium hardness.

*Followed instructions and sample water turned a faint pink/purple color. Added R-0012 to see if color would change and after 10 drops it did.



Anyone have this happen to them like this after draining and filling your spa? Please help this has been bugging me for the past three days. By the way our pool has no issue what-so-ever and when we do our testings with our test kits the colors turn an obvious color.

 

[linen]

It is late and I am not thinking to clearly but I have a theory.

I am theorizing that your FC is higher than 10 ppm and you may have to add even more R-0870 to get a valid reading. If you have an OTO chlorine test (the one that gives shades of yellow for total chlorine) could you use it and tell us what the color is?

From the extended test kit directions on OTO chlorine testing:

You can use this test to get a vague idea of extremely high TC levels. If the sample turns a particularly vivid yellow the TC level is between 5 and 15, light orange is between 10 and 20, dark orange is between 15 and 30, and brown is 30 or higher.

If your's is dark orange to brown then your FC is pretty high and you do probably need to add more of the R-0870.

If the FC is high then this could also explain your strange ph result. First, when FC is over 10 ppm the ph test is not valid. In addition, my understanding is that at high FC levels starting somewhere between 18 and 23 ppm for the Taylor chemistry the phenol-red indicator dye used for the ph test gets transformed into chlorphenol-red indicator which measures PH between 5.2 and 6.6. Some people have reported a purple color when this occurs.

Again, I am tired, but I think this could be the problem you are seeing.

How much chlorine were you adding?

 

[ak.operator]

Unfortunately we don't have an OTO chlorine test kit. We have tried reducing free chlorine levels by draining spa but no success also we tried using Dichlor and also nothing. Any suggestions? And why do I get a purple color when testing for pH after we have done nothing to balance spa water after draining and filling?

 

[yeggim]

Chlorine (Free, Combined) Test

Test unit calls for 25 mL of sample water with 2 dippers of R-0870 until sample turns pink. If pink color disappears, add R-0870 until sample water turns pink.

*Followed instructions and pink color disappeared so added 2 more dippers of R-0870 until sample turned pink.

Test unit calls to add R-0871 reagent drops until pink sample water turns clear then multiplying drops by .2 ppm to find out free chlorine levels.

*Followed instructions and ended up having to add 100 drops of reagent. 10 ppm free chlorine.

100 X .2 = 20 ppm

There's no need to use a 25 ml sample. You can use a 10 ml sample and multiply each drop by .5
Your reagents will last longer that way.

 

[linen]

100 X .2 = 20 ppm

Good catch yeggim!