How often to test & how much chlorine to add daily? Also, vacation upcoming...

[AnnaK]

How soon you can check the chems after an addition depends on how well your pump circulates the water. I usually wait a couple of hours before testing again.

As to how often to test, I check pH and FC/CC every day, TA once a week, CYA once a month after I have it where I want it to be. Because our pool has a lot of splashout from the dogs we refill almost daily and have considerable dilution of CYA and have to adjust it more frequently.

[blessedbeingmom]

Okay, last night at 8 pm our FC was 2 ppm. Using the pool calculator, at 10 pm last night, Matt added enough bleach (1,140 grams) to get to 6 ppm. This morning when he tested at 8 am, the FC level was 4.5 ppm. How does this sound?

[CarlD]

It sounds like you either are still fighting something or miscalculated. I can't figure powder amounts--but bleach and LC I can do in my head...

Had you measured the pool an hour after you added the chlorine, you would know what the FC was then and there. If it was 4.5, then by this morning, you lost nothing.

Meanwhile, I don't know where you are but this season, for unexplained reasons, EVERYONE around the country seems to be using excessive amounts of chlorine--myself included. I've had to add a gallon of 12.5% the last two days.

[blessedbeingmom]

It sounds like you either are still fighting something or miscalculated. I can't figure powder amounts--but bleach and LC I can do in my head...

Had you measured the pool an hour after you added the chlorine, you would know what the FC was then and there. If it was 4.5, then by this morning, you lost nothing.

Meanwhile, I don't know where you are but this season, for unexplained reasons, EVERYONE around the country seems to be using excessive amounts of chlorine--myself included. I've had to add a gallon of 12.5% the last two days.

It wasn't powder that we added, it's just that DH uses the scale to measure how much to add, on the presumption that for 6% bleach, since most of it is water, it's of a similar density to bleach, and therefore 1000 grams is about 1000 milliliters (one liter).

We would have measured it last night again, but weren't sure how long it would take for the chlorine to be dispersed. We plan to check the level mid-day today since it is going to be a hot & sunny day here, and then again this evening. We plan to shock the pool Tuesday night, and then again before we leave for vacation.

We are in South MS, about an hour northeast of New Orleans.

[CarlD]

Why use a scale? I think you are doing it the hard way.

The rule of thumb for bleach is: 1 gallon of 6% adds exactly 6ppm to 10,000 gallons of water.

Since you have 5,000 gallons, you would need only 2 quarts of 6% to get a rise of 6%. 3/4 of that (a quart and a pint) would raise your FC by 4.5ppm.

Did you add 3 pints of 6% bleach?

BTW, if the bleach is 5.25%, substitute 5.25 for 6. If it's liquid chlorine and it's 12.5%, substitute 12.5 for 6.

You don't even need a calculator!

this is based on the formula for bleach addition:
FC added = (1,000,000/pool gallons) * 0.06 * # gallons of bleach, where 0.06 is 6% bleach. Use .125 for 12.5% LC.

[blessedbeingmom]

Why use a scale? I think you are doing it the hard way.

That's DH for you! He specializes in doing things the hard way. LOL! He's very scientific about everything! To be fair, he says the bottle is an odd size, so it makes it hard to measure it. I think we'll find an old pitcher or something and make quart and/or pint markings on it and use it for adding bleach, so we can do it the easy way, but for now, he's still doing it the technical way.
Okay, I was at work today & DH did not test the FC levels this afternoon. They were 4.5 ppm this morning. We swam at around 11:30. At 9 p.m. this evening, the FC was only 0.5 ppm. DH figured the amount of bleach to add to get it back up to 10 ppm and added 2,280 gm (about 2.28 Liters) of bleach. He checked the FC levels again at 11:45 (to allow time for circulation, and our level did not get up to 10 ppm. It only got up to 8.5 ppm.

Stay tuned for tomorrow's edition of "As the Pool (prayerful does not) Turn (into Algae) Again." LOL!

[CarlD]

OK,

That's very revealing. Thank you.

You are clearly fighting something in the water. That's why it's dropping so much. Of course, as I said, EVERYONE around the nation is using large amounts of chlorine this season. You need to add sufficient bleach to bring your FC up to shock level: 15ppm, and keep it there for at least 24 hours or until it stops dropping drastically. It may be as little as 24 hours. After raising the FC, check the water 3x a day and raise it back to 15 as needed. When, after 24 hours, it doesn't drop, or doesn't drop much (especially overnight, when there's no UV to break chlorine down, you can gradually let the FC drop back to the maintenance level which is 3 to 6 ppm and which is where you'll keep it on your normal daily basis.

[Watermom]

That's DH for you! He specializes in doing things the hard way. LOL! He's very scientific about everything!

Um, yeah. I know somebody (who shall remain nameless) but his initials are P.o.c.o.n.o.s. who is just like that!

Stay tuned for tomorrow's edition of "As the Pool (prayerful does not) Turn (into Algae) Again." LOL

Love it! Gave me a good chuckle this morning!

[AnnaK]

Meanwhile, I don't know where you are but this season, for unexplained reasons, EVERYONE around the country seems to be using excessive amounts of chlorine--myself included. I've had to add a gallon of 12.5% the last two days.

Yep, count me in with that group.

I decided to raise my CYA from its normal 40 ppm to 60 ppm which has noticeably reduced the frequency and amount of chlorine additions. I'm running the FC at 5-7 ppm now.

It's been a weird season. Late to warm up, lots of rain in the spring, then a nasty heat wave with no rain at all which is making demands on my well for refills.