I've got something going on in my pool, but I don't know what.
I've got an 18,000 gallon cloud shaped pool with an attached 6' spa. I bought a TF-1000(?) test kit. I've got a Pentair Chlorinator that I use to keep the chlorine level between 5 & 7 ppm. With the amount of evaporation I am getting, plus the splash out I get (the pool gets used often by kids) my CYA (tested twice a week) stays around 50.
three weeks ago, I noticed stains growing on one of the walls of my pool. I checked all my numbers, & everything looked good. FC was between 5 & 7
CC was 0
TA was 70
PH was 7.6
The pressure on my filter had not gone up any higher/lower than normal.
I stepped up the brushing & asked the pool store guys for advice. They suggested I put a measured amount of Black & yellow mustard killer in the pool I did so, but didn't really see any difference in the stains.
So a couple of days later, my pump goes out. I forgot to call my pool builder the day after I found out (thursday - this pool was installed in March) Friday I called, they sent someone to fix my pump Wednesday. So my pool sat with no circulation for a week.
Now the stains were every where. With the pump fixed, I broke out the vacuum. The manual vacuum, the robot stayed in the pool, but had no affect. the manual had no affect. But the brush seemed to do a good job. So I've been brushing my pool daily. I'm kicking up green dust & my filter is knocking it out.
I dumped 7 gallons of bleach into the pool. I checked the chlorine level 5 hours later..... nothing. No FC, no CC. I dump another 7 gallons in the pool, and went to bed.
Three days later, & I've done the same thing a few times & I'm still not reading any FC/CC....
Last two days it's been raining pretty heavy here (Tropical Storm Lee) I don't know if that has anything to do with it.
4 hours ago, I dumped 9 gallons of bleach into the pool I checked the chlorine levels an hour ago.... nada.
It's not possible to use up 20 ppm of chlorine in 3 hours is it?
How soon after I add the chlorine should I test to get an accurate reading of what I put in?
If it helps, I've got a Hayward Tristar pump.