Using 2.5ppm per day, should I bump CYA?

[Lissawku10]

I use liquid chlorine each day for 31k gal. My CYA is 30. I’m consistently using 2.5ppm per day (water temp 84 and high temps between 85-90 each day), so I’m adding 3 quarts (sometimes a whole gallon— I think maybe the strength isn’t as high as it is supposed to be) of 10% each day. I have researched but keep seeing contradictory information. If I bump my CYA to 40, would it use less chlorine?? If there’s a way to not burn through these jugs so fast, I’m all for it!

 

[Flying Tivo]

Yes you can, but have you done an Overnight Chlorine Loss Test??
I would do it before raising cya.

 

[Lissawku10]

Yes you can, but have you done an Overnight Chlorine Loss Test??
I would do it before raising cya.

I should have put that in there. Yes, I’ve checked it twice in the past week to be sure and I’m not losing any overnight.

 

[DeanP66]

If you are in a warm climate and your pool gets lots of sun, you are probably better off with your CYA at 40-50ppm. Although you'll have to bump your FC target level up when you add, you will lose less FC daily than if it's down at 30.

 

[Jimrahbe]

Lissa,

Most pools use 2 to 4 ppm of FC per day... Running your CYA a little higher should drop your use a little, but your FC use will never be zero..

Thanks,

Jim R.

 

[pjt]

2.5 ppm loss of FC is normal. Have you considered a SWG?

 

[Lissawku10]

We have a steel wall vinyl pool, so we don’t really want to do SWG.

 

[Oly]

When I was dosing with liquid I observed a slight drop in FC loss as I increased my CYA from 30 to 40ppm. Try adding CYA in 5ppm additions and monitor your FC loss after a couple days. Your FC target will go up with a higher CYA but your daily FC loss may drop slightly. Owning a proper test kit makes it possible to monitor and manage your water chemistry at this level.

 

[Sunnydaze]

In march, i increased my cya from 40 to 50 and my fc usage went down 1ppm per day. Recently, i increased cya to 60 and am saving an additional 1ppm per day. I'm up to about 2.5ppm fc loss per day now. I'm sure usage will continue increasing through summer but I don't think I'll go above 60 cya. Hoping it'll be no more than 4ppm fc loss at peak.

 

[wireform]

We have a steel wall vinyl pool, so we don’t really want to do SWG.

That's complete misinformation there. With all the chlorine additions daily and almost everything you throw at the water has "salt" so your pool has probably a decent amount in there already. If it hasn't rusted with chlorine it won't with a SWCG. Lots of members here have what you have and some even have the automatic motorized pool cover with it for several years without rusting problems. A well balanced pool chlorine or salt have the exact same probability.