New Pool - Test Results

[mcdickey]

I recently (November 8, 2016) purchased a new home with a pool and due to the time requirements of an ongoing home renovation I just today finally had time to check the water chemistry. It's a 21,000 gallon rectangular in-ground plaster pool with no spa and no water feature. Here are the results with a Taylor K-1005 test kit supplemented with the addition of Taylor K-1515 FAS-DPD chlorine test kit):

- FC 3 using K-1005 DPD test and 30 using the FAS drop test
- CC 0
- CYA 90
- PH 6.8
- TA 60
- CH 250
- Water Temperature is 53 degrees

I am concerned that the PH is so low and am also concerned in the dramatic difference between the two FC test types (3 versus 30) results.

So...What should I do first please? Raise PH seems like the obvious step to me.

Thanks in advance for your thoughts.

 

[PebblePool]

I learn something new every day, Taylor sells a pink DPD drop test in the K-1005, and a standalone FAS-DPD test in the K-1515. I would re-read the instructions on the K-1515 test, and try it again.

What kind of finish is it (i.e. plaster, exposed aggregate pebble or granite, vinyl...)?

I recently (November 8, 2016) purchased a new home with a pool and due to the time requirements of an ongoing home renovation I just today finally had time to check the water chemistry. It's a 21,000 gallon rectangular in-ground plaster pool with no spa and no water feature. Here are the results with a Taylor K-1005 test kit supplemented with the addition of Taylor K-1515 FAS-DPD chlorine test kit):

- FC 3 using K-1005 DPD test and 30 using the FAS drop test
- CC 0
- CYA 90
- PH 6.8
- TA 60
- CH 250
- Water Temperature is 53 degrees

I am concerned that the PH is so low and am also concerned in the dramatic difference between the two FC test types (3 versus 30) results.

So...What should I do first please? Raise PH seems like the obvious step to me.

Thanks in advance for your thoughts.

 

[Jimrahbe]

mc,

I think something is wrong with your FAS-DPD testing method.

If you used the 25 ml sample then to get 30 ppm FC you would have had to use 150 drops...

If you used the 10 ml sample then to get 30 ppm FC you would have to had to 60 drops.

I suspect you need to re-read the instructions.

Please tell us exactly how you were running the FAS-DPD test..

Thanks,

Jim R.

 

[JamesW]

If the fc is really 30, then the dpd test is likely to be bleached out and reading lower than actual.

 

[mcdickey]

Thank you for the responses. I updated my signature to include the fact that the pool is plaster. While this pool is new to me I should clarify that the pool itself is old and was originally built in 1973. I should also add that the water is ever so slightly cloudy. I am not new to pools and successfully maintained the SWG pool at my last house for 6 tears using Troublefreepool. I did the FAS-DPD test as follows:

- Rinse out squeeze bottle and then collect sample water about 18 inches below water surface after running the pump for at least 1 hour
- Rinse the test tube and then fill to 10ml mark
- Add two level dippers of R-0870 DPD Powder
- Stir using SpeedStir while adding drops of R-0871 FAS-DPD
- Add drops counting until water turns clear...I counted 59 drops

I am sure I did the test correctly. I have not used the test kit for 6 months though and it has been sitting in the garage of my rental home. I guess there is a chance the stuff went bad from the storage. Additional thoughts?