I am puzzled by my CH test results of today and am hoping I can get clarifications here.
Two nights ago we had huge amounts of rain. There are overflows builtin to the pool so the excess water drops out. So usually CYA and CH drop after heavy rains.
I figured my CH would have dropped yesterday, as both overflows were pouring out full, but it did not.
(See tests results below)
I ran out of CYA reagent (have some ordered but not in yet).
So yesterday I used the pool calculator to increase my CYA by a bit until the new reagent comes in. I went for 10ppm to be safe which is around what I usually lose after heavy rains.
before rain CH 230 (after rain 230)
before rain TA 50 (after rain 60)
before rain PH 7.4 (after rain 7.6)
before rain FC 1.5 (after rain 2.5) (my handyman added a bit of calhypo 3 hrs before i tested)
before rain CYA 40 (after rain assumed around 50)
I just tested today and the CH test turns very clear yellowish pinkish with 5 drops of reagent, instead of usual light red. When I added 5 more it turned the usual color and it required 25 drops of titrant to turn blue. I repeated the test with half the water in the test tube and 5 drops of reagent and it required 12 drops of titrant to change.
So I am thinking my CH is around 125ppm (25 div by 2)? Am I counting this right or should it be times 2?
I did shock to 20ppm with calhypo yesterday a few hours after increasing CYA...
Today FC is testing at 3
CYA assumed around 50
and CH inconclusive (either 125 or 500)
the pool calculator tells me that the calhypo I added to shock should have brought my CH up by 12?
I ran the CH test twice with 2 different kits...
Does it make sense that the CH remains unchanged 12 hrs after heavy rains but drops by nearly half 24hrs later?
What's going on??
I am using calhypo because my SWG is out of order awaiting parts...