New pool owner. I've been reading a ton about pool chem lately, and I'm trying to become competent and confident enough to manage my pool chemistry. You should know that I'm an engineer, and I'm overly technical and I like things to be precise. As you can probably imagine, I've been thrown for a loop by both the test strips and the DPD testing. I was hoping for a nice digital reading with 1/100th precision for every pool chem component. I've given up on that dream, but I was hoping you guys could help me gain confidence in testing my pool water. So . . .
My pool is gunite/plaster and 25k gals. Saltwater system with Aqua Logic and T-CELL-15. I just aquired the property, and the pool was previously maintained by a pool svc company on a weekly basis. The pool water is crystal clear and not alot of junk gets in the pool. The pool guy tells me that the pH is around 8 or a little over, and that's ok (I know you guys are gasping -- in all of my reading, I've never come across one other person who said that). He said that SWG pools naturally have a higher pH and that's ok. That's my background (over the last 3 weeks of learning and talking to the pool guy). So, getting to the point . . .
I want to correct any issues I have and manage things correctly going forward. Unfortunately, I'm really struggling with the test strips (AquaChek) and even with my DPD test kit (Pentair Pro-II -- Rainbow reagents #2, #3, #3b, #4, #5, #6, and #7). The pool stores uses the computerized method of color-matching. I can't get the test strips to even get close. The FC is at the extreme upper end of 10ppm, so it might even be higher than that. I can't even really tell what color the pH matches best to, if any. The stabilizer seems to match best to 150-ish, and that can't be right (I hope). TA looks like 180-240, but even that is hard to tell. See pool store results below.
I guess I feel a bit better about the DPD test kit, but I still don't have much confidence in it yet. FC appears to be up in the 10ppm range, which is the upper limit. This 10ppm reading (or whatever it is) has happened every time I tested (even when the store said 3.5). pH is still showing around 8 or higher. CH and TA seem to be a tad more dependable since you count the number of drops, and the solution changes color abruptly. I get TA=100 and CH=200 on the latest results.
The pool guy had the pump running 24/7 and the chlorinator at 50%. I actually cut it off for a few days (which apparently got the pool store FC reading down to 3.5), but I'm now running 9am-9pm and at 30%. Still learning there.
I just want some consistency and confidence in my readings!
First trip to the pool store:
FC: out of range
Recommendation: add 4 lbs of pH Down (sodium bisulfate I think), add some calcium. I did this.
Second trip to the pool store:
Sorry so long! Thanks for any help and/or sympathy.