Never had an algae problem before....

[lisak]

I have a 23,400 gallon IG pool with a vinyl liner. I put one of the anchored mesh covers on the pool last fall and have encountered a new set of problems to replace the ones that I fixed with the cover. First time I have ever opened to less than perfectly clear water. I have been battling algae. I keep shocking and scrubbing but after reading assume that I haven't kept the chlorine high enough for long enough. Today I put in 5 gallons of 12.5% liquid chlorine and have been scrubbing. Here are my numbers before adding all the chlorine:

FC 1.8
TC 1.8
CC 0
pH 7.4
Hardness 40
Alkalinity 70
CYA 30

The pool store wants raise my alkalinity but from what I have read on here, I am thinking it is ok? I have already told them I am not adding calcium as I see no need for it in my pool. If I do need to raise my alkalinity, how much baking soda should I add? The pool store lady also wants to test my phosphate levels after I kill all the algae and then add a decreaser? I have never even heard of that. Since it doesn't fit the 3B's that I tend to use, I'm assuming she just wants money? What is she talking about and is that really something I need to do? I'll retest and repost in the morning. Also I seem to remember a chlorine calculator on here from a couple years ago to figure out how much to add, but I couldn't find it when I did a search. Does anyone have a link? Thanks for any help.

Lisa

[daisy11]

Here's a link to bleach calc, save it to your desktop and you can use it whenever you need to. http://richardfalk.home.comcast.net/...achCalc262.exe

As far as the alkalinity goes, as long as your pH is stable, *I* wouldn't adjust it. If it ain't broke, don't fix it! If you want to add baking soda to raise it, add just a cup or two at a time, circulate, and test again before you add more. I don't know anything about the phosphate question, but it seems to be controversial. Perhaps one of the experts here will address that for you.

Try to test your cl level 2-3 times a day and add enough cl to bring it back up to shock level each time you test. How does your water look, and what are your test results this morning?

[CarlD]

I have a 23,400 gallon IG pool with a vinyl liner. I put one of the anchored mesh covers on the pool last fall and have encountered a new set of problems to replace the ones that I fixed with the cover. First time I have ever opened to less than perfectly clear water. I have been battling algae. I keep shocking and scrubbing but after reading assume that I haven't kept the chlorine high enough for long enough. Today I put in 5 gallons of 12.5% liquid chlorine and have been scrubbing. Here are my numbers before adding all the chlorine:

FC 1.8
TC 1.8
CC 0
pH 7.4
Hardness 40
Alkalinity 70
CYA 30

The pool store wants raise my alkalinity but from what I have read on here, I am thinking it is ok? I have already told them I am not adding calcium as I see no need for it in my pool. If I do need to raise my alkalinity, how much baking soda should I add? The pool store lady also wants to test my phosphate levels after I kill all the algae and then add a decreaser? I have never even heard of that. Since it doesn't fit the 3B's that I tend to use, I'm assuming she just wants money? What is she talking about and is that really something I need to do? I'll retest and repost in the morning. Also I seem to remember a chlorine calculator on here from a couple years ago to figure out how much to add, but I couldn't find it when I did a search. Does anyone have a link? Thanks for any help.

Lisa

Your numbers are FINE--don't mess with ANYTHING but chlorine. Your job now is to kill your algae so it stops eating your chlorine.
pH 7.4--PERFECT--Don't mess with it!
CYA 30--PERFECT--Don't mess with it!
CH 40--Anything below 500 is FINE for vinyl--Calcium does NOTHING for vinyl--it's a waste of money to increase it. It will have NO effect on your algae problem. --Don't mess with it!
T/A 70--MAYBE a tad low but that could be measuring margin of error. Unless your pH is jumping around, Don't Mess with it! If you MUST, add 1lb of Arm&Hammer Baking Soda (yeah, baking soda) and no more.

What you need is to get your FC up to 12 to 15ppm and that's going to take lots of LC. One gallon of that 12.5% LC will add about 6ppm to your pool. So add 2 gallons and then, 8 hours later, measure your FC and add LC to get it up again. Do this 3x a day to maintain the 12-15ppm level until your FC and TC are the same (which means CC is 0--what you want) and FC doesn't drop so precipitously.

Basic algae fighting drill...check our stickies.

But don't add anything but chlorine to your pool.

[aylad]

The pool store lady also wants to test my phosphate levels after I kill all the algae and then add a decreaser?

Phosphate removers are one of the latest and greatest ways for the pool stores to make money by taking advantage of people who don't know any better. The only time I would even consider a phosphate remover is if all the conventional ways of dealing with the algae fail miserably--and that's not what's happening in your case. You need to raise your chlorine to 15 ppm and keep it there by testing and adding more to get back up to 15, and doing this 2-3 times daily. Run your pump/filter in the meantime, because the chlorine will kill the algae but the filter is what removes it from the pool. Don't waste the time or money on the phosphate removers.

Janet

[lisak]

Thank you for the help. I thought my numbers looked good too. The water is cloudy this morning. I scrubbed the pool down again and vacuumed. Here are today's numbers:

FC: 7.2
TC: 8
Combined Cl: 0.8
pH: 7.4
Alkalinity: 80
CYA: 20


I dumped in another 2.5 gallons of the 12.5% chlorine and will retest tonight. I had surgery on Wednesday so have been having the pool store test water until I feel well enough. My alkalinity went from 70 to 80 in 24 hours and my CYA went from 30 to 20. Obviously very accurate. Will start doing my own testing tonight! How long do I keep the chlorine levels high? Is there a way to tell? Thanks for all the help and input.

Lisa

[daisy11]

The more often you test and add cl to bring your cl back up to 12-15ppm, the sooner the algae will be killed. If you allow the cl to drop drastically from shock level, the algae continues to keep a foothold in your pool. That's why everyone keeps saying test 2-3 times a day and add cl to bring it back up to shock level. The presence of combined chlorine tells you that the cl is still fighting something (algae) in your pool. Keep testing and bringing it back up to shock level 2-3 times a day until the cl level holds overnight and the CC is at zero. Then you can let it drop to normal levels. It may take a few days, a week, or longer, depending on your pool, how bad the algae bloom is and how consistent you are about keeping the cl level up.

The cloudiness is probably dead algae. As Janet said, keep the pump running 24/7 and it will get filtered out.

The other thing you need along with liquid chlorine is POP...pool owner patience. It will clear up...really, it will!

I hope you have a quick recovery from your surgery...and your algae bloom, too!

[CarlD]

The more often you test and add cl to bring your cl back up to 12-15ppm, the sooner the algae will be killed. If you allow the cl to drop drastically from shock level, the algae continues to keep a foothold in your pool. That's why everyone keeps saying test 2-3 times a day and add cl to bring it back up to shock level. The presence of combined chlorine tells you that the cl is still fighting something (algae) in your pool. Keep testing and bringing it back up to shock level 2-3 times a day until the cl level holds overnight and the CC is at zero. Then you can let it drop to normal levels. It may take a few days, a week, or longer, depending on your pool, how bad the algae bloom is and how consistent you are about keeping the cl level up.

The cloudiness is probably dead algae. As Janet said, keep the pump running 24/7 and it will get filtered out.

The other thing you need along with liquid chlorine is POP...pool owner patience. It will clear up...really, it will!

I hope you have a quick recovery from your surgery...and your algae bloom, too!

Couldn't have said it better--Thanks for saving me and Jan all that typing!

[daisy11]

Couldn't have said it better--Thanks for saving me and Jan all that typing!

No problem, happy to pass on the wisdom from you and Janet and all of the other experts here. I've been there, done that....as many here have!

[lisak]

Just wanted to say thank you. The pool is sparkling clean and so far no return of the algae. Thanks!

[CarlD]

Just wanted to say thank you. The pool is sparkling clean and so far no return of the algae. Thanks!

That's what we LOVE to hear!