My pool is in fuuuuuuullll sun in Central Texas where the highs this week range from 98-100. My pool water hit its new high of 90 degrees today. I see some of you in warmer areas keep your CYA above than the 30-50ppm recommended for a plaster pool (I assume that means pebbletec too) when sanitizing with bleach. Should I still be aiming for the 30-50 range or would you keep the CYA a little higher?
CYA for a full sun pool in a warm climate
- Thread starter frogkick
- Start date
I would start with 30 and see how the chlorine holds up. If you lose quite a bit during the day and less than 1 ppm overnight I would bump it up to 40 and see how it does. You don't want to raise it too high. It is normal to lose about 2ppm FC every day, and more if the swimmer load is heavy. Remember to adjust your FC target higher as you increase CYA.
With a CYA of 50-60, I want a higher chlorine level following the reference chart? I was under the impression levels over about 4ppm were irritating to the skin.
That is a complete myth perpetuated by uninformed pool store people. I spent a week SLAMing my pool 2 summers ago with CYA at 70 and FC at 28. We swam every day and nobody even noticed the FC level. FC at shock level for your CYA is less harsh than FC at 3 ppm with 0 CYA. You could swim with your CYA at 50 and your FC at 15 and you would never notice the chlorine.
Nope. When the ratio between the FC and CYA is the same, the harshness is basically the same. Still way less harsh than a public pool with no CYA and a FC of 1-2ppm.
I know someone on here told me that little shades of yellow daily chlorine test isn't very accurate and that it mostly just indicates the presence of chlorine in water. So to know how many ppm I'm losing per day, should I be using that chlorine test with the scoop of powder daily?
At the start, yes. Until you learn your pool. Then you might be able to use the OTO test usually and the FAS-DPD only a few times a week.
Do both for a while and you will probably be able to discern the shade of yellow that approximately corresponds to your target FC of 9-10. Then you can use the OTO test as more of a quick check to make sure you didn't get a surprise visit from some birds or something that used up all your FC.
My pool water is about 6 weeks old. For now, I'm using pucks to chlorinate and raise CYA. I plan on tapering off to liquid when I reach a desirable CYA level. Our water leans alkaline here so if the pucks bring down pH, that won't be a problem. Does this seem like an okay way to start out a pool? Using that dot test in the TF-100, my CYA is somewhere between 20 and 30, closer to the 20 line than the 30. Sounds like I want to continue to bring it up. I've been aiming for an FC level of 3, because I thought that's what I was supposed to have, so I guess I should be bumping that up to about a 5 for my current CYA?
Round up to the next even multiple of 10 for CYA (example if CYA looks like 15, use chart line for 20, if looks like 21, use chart line for 30). If water is crystal clear, keep in target range, up to shock is safe to swim, and avoid below min. [FC/CYA][/FC/CYA
Quiz time! "CYA is somewhere between 20 and 30, closer to the 20 line than the 30" so according to the chart, what is your target FC range?
We generally suggest using a stabilizer/conditioner product of 95-100% CYA to raise CYA to 30, but if you're holding chlorine and not losing it all to the sun, and going to test FC and add often enough to keep in the target range, your method of adding via tablets is fine, just slower.
Thanks to PoolMath, after putting in your pool gallons, and going to the bottom, we can see that each 8oz puck (throughout it's dissolving life) adds FC 3.9, CYA 2.4, and lowers PH 0.21 so if you have 4x or 5x pucks in there at a time, keep an eye on PH; maintain 7.2-7.8, and never go below 6.8.
Remember that you'll still need to add bleach during this process since it is adding CYA that does not go down, but FC that burns off, so pucks alone can't keep any pool sanitized for long.
Quiz time! "CYA is somewhere between 20 and 30, closer to the 20 line than the 30" so according to the chart, what is your target FC range?
We generally suggest using a stabilizer/conditioner product of 95-100% CYA to raise CYA to 30, but if you're holding chlorine and not losing it all to the sun, and going to test FC and add often enough to keep in the target range, your method of adding via tablets is fine, just slower.
Thanks to PoolMath, after putting in your pool gallons, and going to the bottom, we can see that each 8oz puck (throughout it's dissolving life) adds FC 3.9, CYA 2.4, and lowers PH 0.21 so if you have 4x or 5x pucks in there at a time, keep an eye on PH; maintain 7.2-7.8, and never go below 6.8.
Remember that you'll still need to add bleach during this process since it is adding CYA that does not go down, but FC that burns off, so pucks alone can't keep any pool sanitized for long.
Is there a chart out there or some way to estimate how much bumping my CYA up from 50 to 60 might affect my FC loss? I did the overnight test last night and lost 0 ppm. Today, no one swam and I still lost 6ppm. If I were to go up to 60, any guesses what my FC loss might be at that level?
I got it up to 10 ppm last night after the sun went down and measured it again this morning about 30 minutes after sunrise, still at 10 ppm. I checked it just now and it was at 4 ppm.
That seems a little high ... I usually think about that a CYA of 50ppm will protect about 50% of the FC from the sun each day ... but that is just my thought and may not be completely accurate. It greatly depends on sun exposure and water temperature and usage.
At 60ppm, perhaps you would only lose 40-45% of the FC each day.
At 60ppm, perhaps you would only lose 40-45% of the FC each day.
No swimming today and no critters in the skimmer baskets, but it is triple digit weather, 90 degree water temperature, and unrelenting sun on the pool. I'll recheck CYA in the morning. Maybe I misread the dot and don't have as much as I think I do?
I just retested CYA today under the same conditions - late morning, back to the sun, and holding the tube at waist height. The black dot *is* visible at 50, but baaaaarely. You really have to look for it. I think you'd have to know it's there to see it. It's completely gone at 40, but if we are rounding up, I'm sure the disappear point is somewhere between them. I did the OFCLT two nights ago and lost 0ppm. Last night, I did not do an official OFCLT. I chlorinated around 6:00 pm (when the pool was mostly in shade), the filter ran until 8:00pm and then shut off for the night, and this morning at about 10:00, I measured again and found I lost about 1.5ppm in those 16 hours. Am I wrong in thinking this suggests my daily massive chlorine loss is due to sunlight?
What would you guys recommend? Should I raise the CYA to 60 or is it better to accommodate for the big FC losses at 50 by adding higher amounts of chlorine daily?
What would you guys recommend? Should I raise the CYA to 60 or is it better to accommodate for the big FC losses at 50 by adding higher amounts of chlorine daily?
- May 3, 2014
- 58,308
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Your choice on higher CYA or more chlorine. Most importantly is that you should not let your FC fall below Target at any time during the 24 hour period between dosing.
Take care.
Take care.
Are you saying that it is like this picture #3 at between 40 and 50? If so, round up to 50 and look up your target (and min/shock) for 50 on the [FC/CYA][/FC/CYA].
So your options are:
1) Stick with CYA and eat the extra bleach cost until weather yields
2) raise CYA in increments of 5 or 10 at a time until you get to rounding up to 60, trying very hard not to overshoot the 60 and having to round up to 70 *should but is not guaranteed to lower daily loss*
3) winter cover/umbrellas
If you go #2 you're committing to higher FC's and some people find pools less forgiving of accidental dips under min.
In my personal, non-expert opinion, as long as you're good about keeping FC levels correct, and you don't plan on using trichlor for any work trips/vacations then push it to where it is rounding up to 60 in the hopes it makes a difference your wallet can feel.
There isn't anything inherently wrong about leaving it where it is though, as long as the extra sanitizer expense doesn't bother you. If you somehow continue to see this daily loss with less sun and cooler water - that is something that is inherently wrong.
So your options are:
1) Stick with CYA and eat the extra bleach cost until weather yields
2) raise CYA in increments of 5 or 10 at a time until you get to rounding up to 60, trying very hard not to overshoot the 60 and having to round up to 70 *should but is not guaranteed to lower daily loss*
3) winter cover/umbrellas
If you go #2 you're committing to higher FC's and some people find pools less forgiving of accidental dips under min.
In my personal, non-expert opinion, as long as you're good about keeping FC levels correct, and you don't plan on using trichlor for any work trips/vacations then push it to where it is rounding up to 60 in the hopes it makes a difference your wallet can feel.
There isn't anything inherently wrong about leaving it where it is though, as long as the extra sanitizer expense doesn't bother you. If you somehow continue to see this daily loss with less sun and cooler water - that is something that is inherently wrong.