CYA/SWCG question

[Pam Jo]

Hi,
I've been using the TFP method for two years with much success! Thanks to you all!

I recently (2 wks ago) had a SWCG put in. Pentair Intellichlor model IC40. I had the local pool store install and in hindsight, wish I would have requested the IC60 for my 35,000gal pool. Alas, I did not and hope I'll be ok with the IC40.

I've seen on here to keep CYA levels with a SWCG between 60-80ppm, with 60 not recommended. My pool has always had a CYA of 30ppm and did well using liquid chlorine. My user guide for the SWCG system recommends CYA between 30-50ppm.

I've also read where some experience algae with higher CYA and SWCG.

I will need to raise my CYA quite a bit to get to TFP recommendations and just want to be sure that is correct and where it's best to keep it.

Also, my SWCG is tied into the pump which runs 24/7, so I don't shut it off or have a timer to it. I'm still trying to get the FC level right as it shot up to 11ppm, as we've had a lot of cool rainy weather and it's been covered and the chlorine got a bit high. At setup it was set at 40% and I've turned it down to 20% for now.

So just wanting to be sure CYA 70-80 is really I where I want to be.

Thanks for all your help!
Pam

 

[mknauss]

With an automatic pool cover, if left on the majority of the time, a lower CYA will work just fine. We typically recommend 40 ppm so that when the cover is off for a day of swimming your FC does not fall too much, but you can try 30 ppm CYA if you like. Just test your FC right before you close the cover and be sure the FC is above minimum.

 

[Pool_Medic]

I differ with the above get your cya up to 60 minimum, it’s not only protecting the chlorine gas from UV breakdown but it’s also buffering it to make it less harsh. On another note, you really should get a timer wired between your pump and power source. Your pool only needs to have the pump running 8-10 hrs unless it’s needed to get additional heat into the water. Your pump burns through 1.4-1.6 kw every hour, multiply 14 hrs a day X 30 days X 6 months is 3500 kilowatts. That’s a substantial savings that could go towards a new robot.

 

[Pam Jo]

I usually keep my pool uncovered once the weather warm hits, but it's been very rainy and I've had to drain water off my pool twice, so until summer arrives, I'll keep it covered. But I'll go ahead and raise CYA, because once it gets warm and stays nice, it'll be open most of the time.
Never had a timer on the pump in the 26 years we've had the pool. I'll see if my hubby can get that done.
Thanks for the suggestions!

 

[Pool_Medic]

You never had a timer because old school thinking was pools needed to run 24/7 to get proper turn over of the water, we now know that was more industry gobblygook.