Heat and FC demand

[Karl103]

Hi everyone,

Second year with pool. This summer, as most of us know, has been a hot one. Here in NC we have had over 3 weeks with 90 plus degree days. My pool temp has been 88-90 degrees.

Last readings:

FC 3.5
Ph 7.6
TA 60
CH 250
CYA 70
Pool looks great - crystal clear

Turned my SWG up to 70% over 15 hours run time - usually this gets FC up over where I like it for this level of CYA then I slowly back down as tolerated.

My question- I have been noticing this summer higher chlorine demands for pool. Running my SWG about 20% higher to maintain FC this summer compared to last. I realize lots of things can effect this - bather load, contaminants (although I think these are not an issue as my FC has never gotten below 3-4), sunlight. My question- does the heat affect FC consumption? Or, maybe it’s just my kids are on the pool more ?

Be curious to see what others think about factors related to our really hot summer.

 

[jblizzle]

Warmer water can certainly help algae grow more thus increasing the demand some. But I would think higher usage would be a greater driver.

 

[KarenNJ]

I was just reading an article about warm water temp and higher risk of algae. Have you done a OCLT just to make sure you don't have some hidden algae depleting your levels?

 

[Karl103]

Yeah- maybe I’ll do an OCLT just to be sure but man it has been HOT. I kinda think we just have been swimming more. Also, there has been a lot more evaporation in this heat - thinking excessive evaporation contributes too. We all know the chemistry but I still think heat, for multiple factors effects FC demand.

 

[Microsprint73A]

Yeah- maybe I’ll do an OCLT just to be sure but man it has been HOT. I kinda think we just have been swimming more. Also, there has been a lot more evaporation in this heat - thinking excessive evaporation contributes too. We all know the chemistry but I still think heat, for multiple factors effects FC demand.

Yeah- maybe I’ll do an OCLT just to be sure but man it has been HOT. I kinda think we just have been swimming more. Also, there has been a lot more evaporation in this heat - thinking excessive evaporation contributes too. We all know the chemistry but I still think heat, for multiple factors effects FC demand.

I have noticed a larger demand this year as well. Mooresville, NC.