Dropping 4-5 FC a day

merc123

Bronze Supporter
Aug 2, 2019
106
Georgia
Pool Size
6900
Surface
Vinyl
Chlorine
Liquid Chlorine
I’m dropping about 4-5 FC per day. I consistently add around 40 ounces of 10% bleach per day. If people swim I end up with between 1-2 FC by sunset. If no one swims I’m around 3.

My pool At 6500 gallons gets full sun from about 8:30-7:00. CYA was 50 a week ago. Temps have been 82-86 in the water. Overnight test earlier yielded no loss. Water is crystal clear and clean.

Is this excessive use? I’ve tested daily so I could establish a pattern so I can do it weekly. Should I had more CYA?
 
More people in that volume of water will consume FC especially when the water temps are that warm. Raising CYA above 50 will not help significantly. Your overnight test confirms your water is clean. Best to keep your FC in the target zone and bump it up if you expect a party. If you have a way to shade your pool it will help. You are doing the right thing keep it up and realize you are at peak season now.
 
Last edited:
I have a couple of questions for you:

Are you testing again after you add chlorine to see where you end up? If it is right where you expected, then you can assume you have the right water volume.
Are you sure about your CYA level? That’s a tricky one.
What are your other test results?

Hot sun and heavy use will certainly eat up the chlorine, but I would expect it to hold up a bit better with that CYA level.
 
I have a couple of questions for you:

Are you testing again after you add chlorine to see where you end up? If it is right where you expected, then you can assume you have the right water volume.
Are you sure about your CYA level? That’s a tricky one.
What are your other test results?

Hot sun and heavy use will certainly eat up the chlorine, but I would expect it to hold up a bit better with that CYA level.

I thought about that. I have not tested after adding. I’ve tested CYA a lot. It’s definitely above 50 and probably closer to 55. My pool logs are in my profile.
 
For cya above 50 then round up & count it as 60 so target 9 & see how things go -
dont let it get below 5 unless u want things to grow ?
 
Alrighty so I tested this morning. I added 40 ounces last night to get an FC if 8. I’m showing 9.5 and I retreated CYA. It has dropped to 35. So I need to reboost CYA.
 
I have the same type of pool (around 6900g)- full sun all day - my CYA is around 50 and I keep my FC around 6-8 based on pool math. I have found added it at night really helps - I was adding it around 9am every day and it was down to between 3-4ppm the next morning. Overall, I've learned - 3 cups of 10% liquid every night keeps the pool generally between 6-8FC...I'll bump it up about 30 mins before I have more than just my kids planning on swimming...
 
I'm keeping an eye on it. I added CYA today. I try to add it at night once the sun goes down. I was also running my pump alot which aerated the water. From my aquarium days we used to aerate water to remove chlorine/chloramine from the water prior to adding so I may be over aerating and losing chlorine that way?

Jun 4, 6:37 AM (sun was coming up, but no direct sun exposure yet)
FC: 9.5
CC: 0
CYA: 35

Jun 4, 9:56 AM
FC: 7.0
CC: 0
CYA: 50

I've had about 5 kids swimming since about 10:30 so we'll see what it is after they're done.

Jun 4, 2:50 PM
Kids done swimming
FC: 5.0

Added 25 ounces of 10% to bring it up to 8 According to the app.

June 4, 5:15 PM
FC: 6.5
CC: 0.5
More swimming

Jun 4, 10 PM
FC: 4.5
CC: 0
Added 33 oz of 10% to make FC 8.5.
 
Last edited:

Enjoying this content?

Support TFP with a donation.

Give Support
This brings up a sorta different question for me. Like those above, my pool also gets continuous sun from 7:30 a.m. until around 8:30 p.m. I'm new to chlorine-just completed my Baquacil conversion this week :giggle:. I have been adding my chlorine in the evening after the sun goes down, then testing first thing the next morning before the pool gets any sun. I don't remember reading any recommendations on when to add and test. Am I doing this right? Why or why not? Educate me please. I sometimes overthink things (I think I just heard my wife laugh!)

I converted to chlorine to keep it simple and enjoy the pool, after three years of fighting the pool and it's Baquacil demons. Thanks in advance for any help you can offer.
 
Updated my above post. FC is at 5 now after kids are done swimming. I added 25 ounces of 10% to bring it up to 8 by the app because I have other kids coming over later and they're probably gonna swim as well. I'll test it again before they swim to make sure it's to 8.
 
Last edited:
How did you add the CYA? It takes forever to dissolve so I’m impressed that you raised it that much in a little over 3 hours.
 
Ghall, congrats on your Baquacil conversion! did you take picture?

I have a SWG, so I don’t have to add chlorine daily. But when I do add it, it’s usually in evening.
 
I’ve got some hanging in mine now. It has been too rainy to mess with it, so it should be nice and squishy by the weekend. I usually swim around with it, squishing as I go.
 
  • Haha
Reactions: carnivalday
Are you testing your other levels too? What are they?

Not sure what your weather has been like, but you are going to lose more to the sun and certainly with people in it. How many people? I’m assuming they have sunscreen on? Contaminants will eat up chlorine too.
 
Are you testing your other levels too? What are they?

Not sure what your weather has been like, but you are going to lose more to the sun and certainly with people in it. How many people? I’m assuming they have sunscreen on? Contaminants will eat up chlorine too.

PH and CYA are fine. It rained yesterday which dropped it a few points. We usually have 5 people swimming in it. Not much sunscreen but some.

At this point it looks like 40’ounces per night is what I need regularly. Just seems like a lot when I see not having to add chlorine but every few days.
 
Where are you seeing that you shouldn’t have to add chlorine daily? Unless people have a SWG or some other form of automated daily dosing, you should expect to add chlorine daily.
 

Enjoying this content?

Support TFP with a donation.

Give Support
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.