Best CYA Level for Lots of Sun - Location Hawaii

[smallpooldad]

Approximately 12 Hours of sun a day. Add liquid bleach every night to 9000 gal pool. It goes from 5 in the morning to 1.5 in the evening. CYA level is approximately 30. What level CYA would be ideal at these lower latitudes to reduce CL usage.

Any help would be appreciated.

[CarlD]

If it were me, I'd start by raising the CYA to 40ppm, try it for a few weeks, and see if chlorine holds better. If not, I'd go to 50ppm and try for several weeks. If it STILL didn't hold, I'd think long and hard before going to 60ppm, but personally, I'd never go higher than that.

That's all IMHO.

[smallpooldad]

Thank you,

I'll go to 40 and let you know how that does. Then anyone from Hawaii will at least have an idea of where to go on this.

One final question, what would be the ideal drop other than zero in the level of chlorine for a not heavily utilized pool? I realize that the answer might be a little difficult as it is sun/UV dependant but maybe someone from Mexico City (around the same latitude), S.Cal or Arizona might be able to give some numbers.

Finally I'm worried about Walmart's stock price, it might drop if I stop going there for my truck load of liquid chlorine.

Ah, decisions decisions.

[Sherra]

One final question, what would be the ideal drop other than zero in the level of chlorine for a not heavily utilized pool?

That's going to depend on your CYA level. See Ben's Best Guess Chart.

[chazas]

I built a pool when I lived in Honolulu and ran it at CYA of 40-50ish. I wouldn't raise your CYA level too much or you'll have to keep a higher chlorine level - and bleach is a lot more expensive in Honolulu! (I could never get over how much Times charged for a little bottle of bleach - Big K and Walmart were the places to go, even though I hated both stores.)

I wonder if you don't have something else going on - like fighting some algae that's eating up your chlorine?

[aylad]

I'm in Louisiana, which is hardly Hawaii, but my pool is in full sun all day in 90-100 degree temps, and I keep my CYA at 80-90. This generally requires the addition of 2 gallons of bleach twice weekly, even in the summer when I have a pretty big kiddie swim load.

janet

[smallpooldad]

Chazas,

As you lived in Hawaii what was your daily chlorine consumption assuming you used liquid and what was your CYA, adjusting your figures for a 10,000 gal pool? This will then give me some idea as to what is normal.

Did you need to put acid in every day to bring the ph down or did you just let it maintain a higher level?

Looking forward to your reply and thank you for your post.

[chazas]

I don't have my "pool book" any more, but to the best of my recollection I ran the pool at around 40-50 PPM CYA.

I tried to keep a minimum FC reading of 3 PPM. I had a 17,000 gallon pool. As best as I can recall, I think I used a couple of the smaller bottles of bleach every 3 or so days. But I don't remember exactly - it's been about a year and a half and I don't have a good memory for numbers.

Bleach did keep my pH on the increase - to the best of my recollection, it would usually go up to 7.8 or a little more during the course of the week, and I'd add about 3 cups of muriatic acid (available from the Ace hardware store on Kaimuki) on the weekend, which would bring it down to 7.5ish. The only time I ever had to worry about increasing pH was when I returned from a vacation after having used a floater with pucks. But I tried to avoid that because it tended to increase my CYA pretty dramatically.

Honestly, I don't think being in Hawaii should impact your pool care regimen too much - summer on the Mainland can have much more extreme conditions.

[smallpooldad]

With CYA now at 50 ppm, CL is dropping from 5-3 over 24 hour period. This requires 40 oz bleach a day or 2gals and 24 oz a week. I am planning on raising it to 60 ppm to see if that further reduces the chlorine need. At that point I will not raise it any higher.

Add 8 oz a day of muriatic acid to keep the pH at 7.3-7.4 for iron stain control.

Will advise on results.

[DavidD]

Boy that's ridiculous. If I were you, I'd trade my house and pool even for one in say, middle Tennessee and let that poor sap deal with it......
Interesting enough, I have raised my CYA to 50 as well and have noticed identical FC loss as you, about 2 ppm a day on a cloudless day. This surprises me as I thought the UV degradation would be slightly higher at the lower latitude. Let us know how 60 works for you.