FC Loss per day without CYA

[unkyjoe]

Greetings,

New pool and have not added CYA yet so it is at 0. Will be adding 32oz over next few days via sock method to get to 40 I understand this can take a week or more to get the levels up?

Yesterday I tested for FC and it was not even registering, I added 5 cups of 8.75 bleach and tested 30 minutes later, FC was up to 5.

Tested this afternoon for FC and it was back down to 0 in fact the color never even changed.

Today was cool, sun was out full till about 2pm my time, now cloudy.

Pool gets full SOUTH TEXAS sun from 7am till about 5:30 pm when the sun goes behind the house.

Is this normal FC loss for that period of time? How much will the CYA help to prevent this much FC loss?

Thanks for helping me understand this a little better.

 

[Casey]

It's completely normal.

Look at CYA this way...

Sunscreen for chlorine. It protects it from the sun. You need it and you should add it ASAP!

 

[jblizzle]

With no CYA in the water, you will lose 50% of your FC to the sun in one hour ... So in 3 hours you would be down to 1/8 left, 4 hours 1/16, etc. So your loss is not surprising.

With a CYA in the recommended range you should expect to lose ~50% of the FC in a day instead of an hour. You should see around a 2-3ppm loss each day.

 

[unkyjoe]

Thanks guys, going to get CYA right now.

P.S With the amount of sun I get from 7am to 5:30pm what would be my target for CYA The pool calc says 40. But with the heavy sun load we get during June-Sept do you think it would hurt to go higher?

I will not be using the pucks, only bleach in the pool so there will be no additional CYA added other that what I add.

Thanks

Any benefit to covering the pool with the Intex cover when not in use? As far as Chlorine loss goes.

 

[imwarren]

Start at 40. Once you get a good grasp of how it is using fc then you can bump it up but never let fc drop below the level on the cya fc chart
The cover will cut fc loss dramatically by blocking sun and keeping stuff out of pool

 

[unkyjoe]

Ok, I added about 2lbs of CYA via sock yesterday and ran the pump for about 4hrs.

I also added Bleach during that time to bring it up to about 5ppm.

Tested FC a bit ago and still at 5ppm. Gonna see how much I loose during the day so will test again around 6pm my time when I turn the pump back on for another 4hrs.

The CYA has pretty much disolved now so I am going to assume on the pool calc that the CYA is at 40ppm for my calculations. I will test the CYA next week as I only have enough chem for one more test.

No pucks! Only bleach. What should my loss be per day of FC? 1-2ppm or will I not know this till I test FC this evening?

Forgive my newb questions, just trying to wrap my head around all of this.

Thanks. P.S the PH dropped below 7.2 should I be concerned or let it rise back on its own, I need to add some more water to the pool today and I assume the PH will rise back on its own.

Thanks

 

[ping]

Can you post all of the test results? I'm going to say you should raise the pH some chemical addition, but we would have more to say if we see all the tests results.

If all is well with the pool, you should expect to see a 2 to 3 point loss of chlorine in a day. If you use a cover, then you might lower the loss to around 1 to 2 points per day.

 

[unkyjoe]

Here are the results

FC=5
PH=7.2 came up from 6.8 last night
TA=90
CH=110
CYA=40 presumed, added 2lb of CYA last evening

Water is crystal clear and can see the bottom very clearly.

 

[ping]

I wouldn't bother to raise the pH and let it rise on its own. Everything else looks good.

 

[unkyjoe]

Ping, thats what I thought as well, leave the others alone and see how my Chlorine does over the next few days so I can estimate the chlorine demand.

Kudos to everyone who has helped answer these questions for me this board has been a wealth of information.

 

[unkyjoe]

Here are my reading this morning.

FC=3-5ppm
PH=7.2

We swam a little last night, the pool water is clear and it was a sunny 92 degree day.

So it appears as if the CYA has taken hold and is now doing its job preventing chlorine loss.

I like that, but will continue to monitor the loss daily until I get a better understanding of how all of this works together.

I also added some fresh water yesterday as well.

What I dont like is the type A filter I have, that thing gets brown with dirt and I clean it daily even though it only runs 4 hours per day. On my old AGP I had a Hayward Sand filter. but alas it sat out in the rain for 6 years and ants decided to make the motor their home, thus rendering the pump useless.

I guess a 2650 is in my future :lol:

 

[Richard320]

Here are my reading this morning.

FC=3-5ppm
PH=7.2

We swam a little last night, the pool water is clear and it was a sunny 92 degree day.

So it appears as if the CYA has taken hold and is now doing its job preventing chlorine loss.

I like that, but will continue to monitor the loss daily until I get a better understanding of how all of this works together.

I also added some fresh water yesterday as well.

What I dont like is the type A filter I have, that thing gets brown with dirt and I clean it daily even though it only runs 4 hours per day. On my old AGP I had a Hayward Sand filter. but alas it sat out in the rain for 6 years and ants decided to make the motor their home, thus rendering the pump useless.

I guess a 2650 is in my future :lol:

Yeah, just keep track of things and you'll learn your pool's appetite pretty good. By the end of July (August if you're dim-witted) you'll be able to predict your test results before you test and probably be within 1 drop on all of them. pH within .2