Should I raise my CYA Level

[Woodberg]

My pool is currently using approximately 4ppm of FC each day, about 182 oz of bleach. My CYA is 40-50. Overnight I am losing .5-1 ppm of FC and the pool is clear. I'm in Houston and its been extremely hot and dry for the past month or so. The pool water temp was at 92 degrees yesterday. We also have a really high bather load with about 6 neighborhood kids.

I was wondering if I raised my CYA level to 60-70 would that help me use less FC each day? I know that's a little higher that what is recommended, but with our temperature and bather load, I was thinking that might help. Also, given the above stats, do you think 4ppm of FC is too much to be losing in a day?

 

[frustratedpoolmom]

I've been losing that too. My normal loss is 1ppm or less during the daytime....because our swimmer load is light and I usually have the solar cover on during the day to cut down on FC loss (when the pools not in use.)... So the other day I rechecked my CYA, thinking it had gotten too low with recent frequent rains, but nope that was fine. Then a couple more days and I was worried something else was happening...but it's been soo hot here Mid 90's all week and the pool temp was in the 90s. So I've been leaving the cover off to keep the temp down, and we've been in the pool each day, several times a day with friends too(not the norm use for sure). I was worried about the excessive loss so I checked my overnight test too, and it was 1ppm.

I think it's normal, with the temps, the use etc. I'm not sure if higher CYA would be beneficial or not, I just wanted to share my recent experience with you.

 

[JasonLion]

Raising the CYA level will reduce your chlorine lost to sunlight, but it won't reduce your chlorine lost to swimming. A bunch of kids swimming for hours can use a significant amount of chlorine. My guess is that much of your chlorine loss is to swimming. If you happen to have a day when they aren't swimming, you can confirm that.

 

[Woodberg]

Do higher temperatures contributed to higher FC consumption or is it strictly sunlight?

 

[JasonLion]

Yes, higher water temperatures causes chlorine to break down more quickly and algae to grow more quickly, so you end up using more chlorine.

 

[Guest]

You have an ozonator. Ozone will destroy chlorine and vice versa. Often there is a much higher chlorine demand with ozone than without. Turn off the ozone for a week or two and see what happens.
CYA will have no impact on FC destroyed by ozone.

 

[anonapersona]

Houston has been having ozone problems... will smog type ozone destroy chlorine as well?

I am in Houston also and was wondering the same thing about raising CYA. I am now at CYA of 40 and I am going through a small jug 96 oz of 6% bleach every day.

I have already scaled back the waterfall to run 2 times for 30 min in early morning and early evening instead of 3 times for 1 hour each morning, noon, and evening. I can't turn it off totally as the birds do use that for water and bathing (yes, I know, an ammonia source but I like seeing the birds there) and I have to keep the mosquitoes and algae washed out of there (yes, into my pool, but what else can I do) and I do realize that the agitation of the waterfall probably adds to chlorine loss, probably as much as a bunch of kids would.

I am seriously considering turning the automatic chlorinator back on to add a few pucks to the pool. Going up to 50 or 60 sounds like it might be helpful and I ought to be able to calculate exactly how many pucks that will be, turn it on the lowest setting and let it help me keep the chlorine while it is so hot.

How hot is it?..... third day in a row that I see 106 as exterior temp as I am in my car, on the road and even in the shade. They "claim" it was only 104 the other day (my car said 106) but they take that temp measurement out in the middle of a field of grass.

 

[gsmornot]

I'm new here but my advice would be to leave the CYA at the current level. You may be using more bleach at the moment but this will slow down as the weather changes. Having a high CYA at that point would not be a benefit to you. So, looking long term I would suggest staying where you are and hope the weather gives you a break time-to-time. That's where I'm at currently with mine.

Average this past week has been 97 degrees with pool staying around 91 degrees. When all the kids are in I use 7ppm for the day but if they don't swim it's more like 2.5-3 which requires very little chlorine to manage. Hang in there.

 

[Buggsw]

Neither of you seem to be losing at a high rate considering the weather conditions and bather loads. I don't think raising your CYA will do a thing for you.

Keep your water circulating for longer periods during high temps to keep the water cooler. We've been running 105 to 109 for several days now and I run my pump 12 hours from 4 pm to 4 am. My water temp goes from 76 in the morning to around 82 during the day. Nice and refreshing.