This is a follow up from this post :
I need to know if this is a possibility :
I am poor with chemistry, so I want to think in simple form.
Chlorine is supposed to be "spent" or converted to other form when it oxidize contaminants in the pool.
If I get contamination that can not be oxidized at say 3.5PPM FC ( CYA at 20 ) , will the chlorine remain in its initial FC form ?
I am thinking of a battle scenario. If chlorine can't kill the contaminants, it doesn't do its oxidizing work right ? In that process I am assuming it doesn't get "spent"...... is this possible ?
6 divers spent some time in my pool Sunday nite, 18 Jan 2009, completed their training at about 7PM.
I noticed the water lost its sparkle, like becoming very mild cloudy.....ooopppsss...I don't like it. FC 2.5 , CYA 20.
So I thought those are more of visual contaminants from the divers, the kind that my filters will take care of.
I dumped 1 liter of 12.5% chlorine ( should raise by 1PPM ) as a precaution...then it rained so hard till next morning, part of my city got flooded. This is the hardest rain I seen since 2007. I do not know how much water was added to my pool. The overflow pipe sent excess water from the balancing tank direct to the drain.
I set the main pump to run non-stop that night and also the trolley pump gets into action. I was sure by tomorrow night the water will be clear again. 8 hours later FC went up to 3.5. 50 hours later and already 8.3 times total pool water turnover and no chlorine loss at all. I had 2 tablets of Di-Chlor dissolving slowly since 18 jan. I really hate when troubleshooting with tablets in water screwing up my calculation. Any how, 50 hours of pumping and no rain and I am not seing improved result even with 2 pumps running 24 hours non stop, its a cause for alarm. Sand & cartridge filter pressures did not increase at all after the 18th Jan divers out of the pool and even the heavy rain from midnight to 6AM.
My new method which I impleted early Jan, have worked well before the 18th :
"If more than 3 divers use the pool, run the pump non stop till next day, so its 24 hours instead of usual 12-14 hours with no bather load. If on top of divers came heavy rain, run the pump on trolley 9PM to 6AM along with main pump.
If bather load more than 5 divers, I run main pump 24 hours and trolley pump 9PM to 6AM, rain or no rain.
If rain hard only and total duration for the rain is more than 3 hours, I run main pump 24 hours.
I need main pump because the ozone is linked to it."
Between 2nd Jan to 15 Jan, it has been raining very often, but none been as bad as on the 18th.
The pool had been contaminated by 20 divers total, with one day 5 diver in one go and less than 10 swimmers. Average time a diver spend in the pool is 3 hours. Never between these dates the pool loose its sparkle.
So this morning at 06:45AM, I get my pool boy to dump 8 liters of 12.5% bleach, hoping to raise to 10 PPM. CYA is 20.
No rain. FC went up to 10.5 at 18:45. At 02:30PM, the main pump cartridge filter shoot up from 8 psi to 9.5 psi, that is 1.5psi in only 8 hours with no rain and diver. Water turned a bit "whiter" mid day. Slime bag replaced with new washed ones, but nothing extra dirty on it. So I am killing the baddies now. At 10:55 PM FC down to 9.5. So in 4 hours without sunlight, I loose 1 ppm already.
The final question is :
Is it possible that at 3.5 FC when chlorine don't kill tough baddies, chlorine simply stay "put" ?? I thought slowly it will kill baddies and consume itself overtime.
This is how it looks like when it loose the sparkle Jan 8th, 10:20pm.
Photo data as follows.....
Speed 1/20 sec. ISO 200. F Stop 3.5. Focal Length 18mm. No flash. Canon 20D. Cheapo original lens. No tripod.
Pool light color temp : 4,000k HID Metal Hilade. 2 x 150w single lamp in the photo zone. Taken 18jan 10:20PM.