High chlorine

[greser]

My Cl- keeps going up despite decreasing chlorinator from 45% to 35%. Most recent readings: FC 16.5, ph 7.8, TA 70, CYA 70, salt 4000
One month ago: FC 9.5, pH 8, TA 70, CYA 40, Salt 3800

I added conditioner and turned down chlorinator. Salt and Cl both increasing.

Anything I can do ? Does it matter?

Thx...Greg

 

[Msch99]

Salt doesn’t increase, probably the margin of error in test kit.

Cooler temps and less direct sunlight reduce CL burn off. Adding cya saves CL too.

So just keep an eye and reduce swg % as needed.

 

[Oly]

Turn off your SWCG for a couple of days and wait to start it until your FC falls just below 10ppm and note your FC ppm. Before you do restart your cell reduce the number of hours it runs per day and reduce the % if the FC level rises after 24 hours.

 

[Newdude]

in the tail end of the extended season for the warm climates, daily FC loss decreases dramatically from the lower sun angle and shorter days. Those of us up north saw it a month or two ago, now it’s your turn.

I found it easiest to just turn the system off for several days once the demand dropped because if I produced anything at all, I broke even and it stayed where it was. I’d be down to 5% by the time I closed.

Is this system new this year for you, or did the it just usually work and the ‘problem’ snuck up on you this year ? I ask because if you or it is new, I wanna get a head start on next year while you practice on easy mode. Right now when you screw up, you overproduce and no harm is done. A GREAT problem to have. In the spring it’s the exact *opposite*. You’ll start low and be on the lookout for all the times the daily demand increases and the cell no longer matches. If you miss one for a few days, boom, swamp. So plan on paying close attention next year to the demand changing. When possible aim a bit above target to buy some wiggle room. After a season or two it will just be second nature

 

[greser]

Thank you for all 3 replies. I didn't get email notification this time of them.
This is not a "new" problem, I've just started paying closer attention. I would take pool sample into the store and they never mentioned elevated Cl- levels.
I'll turn off the SWG% for awhile and decrease run time and monitor.
The pool water looks great otherwise...Thx

 

[Newdude]

This is not a "new" problem, I've just started paying closer attention

Gotcha !! And you are WELL served paying attention.

I would take pool sample into the store and they never mentioned elevated Cl- levels

You have a great test kit, so use it. We can walk you through *anything* with good data to start with. The pool store tests and advice are both question marks at best, and usually terrible.

 

[greser]

Decreasing SWG% to 0 for 1 week did the trick. Today Cl- is 5.5 and everything looks good. I'll turn it back on to 10% and monitor....unless anyone has a "magic autopilot" button I could use...

 

[Phookinl]

Some of the more expensive chlorinators claim to do exactly what you ask by monitoring the ORP of the pool water and adjusting chlorinator output as required. Problem is that the systems are very expensive, generally have poor reliability, high maintenance costs, ORP probes are hundreds of dollars to replace and the high levels of stabiliser in outdoor home use pools tends to mean that the ORP controller is actually poorly suited to the task. In short they're a money sink and they don't actually work very well. Keep it simple, learn from the very experienced users here and you'll get on top of it very quickly.

I notice that your analysis results include a pH of 8, that's a little high and at that pH only a small fraction of your free chlorine is actually effective, so if that's a common state of affairs, the high free chlorine levels may have been doing you a favour. You do want your pH and chlorine to be working together to make sure that the chlorine you have is actually effective and the lower you run your free chlorine the more important that is. There are lots of good threads on TFP about managing your pH, alkalinity and FC, it's worth a read to minimise the amount of bouncing around you do adding acid and bicarb all the time.

 

[poolnoobgrandma]

in the tail end of the extended season for the warm climates, daily FC loss decreases dramatically from the lower sun angle and shorter days. Those of us up north saw it a month or two ago, now it’s your turn.

I found it easiest to just turn the system off for several days once the demand dropped because if I produced anything at all, I broke even and it stayed where it was. I’d be down to 5% by the time I closed.

Is this system new this year for you, or did the it just usually work and the ‘problem’ snuck up on you this year ? I ask because if you or it is new, I wanna get a head start on next year while you practice on easy mode. Right now when you screw up, you overproduce and no harm is done. A GREAT problem to have. In the spring it’s the exact *opposite*. You’ll start low and be on the lookout for all the times the daily demand increases and the cell no longer matches. If you miss one for a few days, boom, swamp. So plan on paying close attention next year to the demand changing. When possible aim a bit above target to buy some wiggle room. After a season or two it will just be second nature

Yes, this time of year we can adjust SWG percentage and runtime to address over production issues.. come spring it's important to remember (I've learned the hard way) that the SWG WON'T CATCH UP. Test frequently as you dial up production, and have LC on hand for those times that the system has fallen behind.