4ppm FC Loss after heavy rain

[beechjetdriver]

Just switched to the BBB method from tricolor. For the past week, I've been trying to figure out how much FC my pool loses/day. It looks like it normally is 2ppm/day. However, It's lost 4ppm FC since yesterday. The weather yesterday was cloudy with heavy rain and thunderstorms from yesterday evening through this morning. The rain added about 1.5 inches of water to the pool since yesterday. CC's are still at 0. The FC level is still coming down from shocking that I had to do last week. My question is can heavy rain dilute the water or create a larger FC loss/day than normal? Here's the test results form this morning:

FC-13
CC-0
TC-13
TA - 150
PH - 7.8 (not accurate because of high FC)
CYA - 52
CH - 170

 

[woodyp]

Does rain dilute chemicals in water------------yes
Can the particulates and dust with the rain raise Fc loss-------------yes
Does FC loss speed up when at shock levels and coming down-----------------yes

 

[beechjetdriver]

Thanks!

 

[pepsiholic]

Just to reiterate what woody said, it is perfectly normal for high FC loss when shock levels are coming down. I lost 11 ppms on a sunny day drifting down from shock levels, but then maintained it at a steady 5 for my cya levels by dosing nightly.

 

[beechjetdriver]

Just to reiterate what woody said, it is perfectly normal for high FC loss when shock levels are coming down. I lost 11 ppms on a sunny day drifting down from shock levels, but then maintained it at a steady 5 for my cya levels by dosing nightly.

Ok, I was a little surprised since it's been a couple days of 2ppm loss (coming down from shock), then all of the sudden I lost 4ppm. I'm guessing it was from the 1.5 inches of rain water that was added to my pool last night. Thanks for your help!

 

[Diver]

on other hand on rainy day you get less UV so you loss less FC, so it somewhat balances out the organics brought down by rain

 

[frogabog]

On cloudy days I loose far less chlorine than cloudy and rainy days. There's a plethora of both around here, cloudy days I can skip dosing one whole night and through the whole next cloudy day. Rainy & cloudy days I usually have to dose so the pool can make it through the whole next day.

 

[gsmiley]

You guys answered my question. I usually lose 2.5 ppm a day, but suddenly been losing 4 then it went back to 2.5 now at 4 again. We are having a very hot and rainy Monsoon season this year, Guess I have to deal with it.