Lost (attempting SLAM)

[kmaloney18]

A little less than a year ago our pool started having algae, then a solar pool cover was added to try to avoid heating the pool for a comfortable swimming temperature, though it was never clear enough after that to use. Cover was tossed, close to $1000 was spent on chemicals, but "we" were never able to get it blue again, minus a day or so after large volumes of liquid chlorine &/or di or trichlor shock being thrown in randomly (I'm having a hard time getting exact information.)

A couple months ago the CYA was at about 90, but after the winter rain, these were values on 2/9/15:
FC 0.25ppm, pH 8.4, TA 100, CYA 42, Ca Hardess 625. Then...

2/12/15:
-10:45pm: pH 7.6, FC 17.0, CC 1.5, TC 18.5, Added 0.75 gal muriatic acid & 2.5 gal liquid chlorine

2/13/15:
-9:10am: Fc 10.5. Cc 1.0, Added 1 gal chlorine
-2:50pm: Fc 14.0. Cc 2.0, Added 0.33 gal chlorine
-8pm: Fc 14.5. Cc 2.0, Added 0.25 gal

2/14/15:
-12:15am: Fc 14.5. Cc 3.0, Added 0.25 gal chlorine
-8:30am: Fc 13.5. Cc 1.5, Added 0.5 gal chlorine
-5:45pm: Fc 14.5. Cc 1.5, Added 0.25 gal chlorine

2/15/15:
-11am: Fc 11.0. Cc 1, Added 1 gal chlorine
-3:30pm: Fc 16.5. Cc 1.5
- 5pm: Added 0.25 gal chlorine
-9pm: Fc 16.0. Cc 2.0

2/16/15:
-10:45am: Fc 12.0. Cc 1.5, Added 0.65 gal chlorine
-12:45pm: Fc 18.0. Cc 1.0
-8:45pm: Fc 15.5. Cc 2.0, Added 0.25 gal chlorine

2/17/15:
-10am: Fc 13.5. Cc 2.0, Added 0.5 gal chlorine
-2pm: Fc 15.0. Cc 2.0, Added 0.25 gal chlorine
-9:30pm: Fc 13.5. Cc 2.5, Added 0.5 gal chlorine

2/18/15:
-9:30am: Fc 14.5. Cc 2.0, Added 0.25 gal chlorine
-4:15pm: Fc 15.5. Cc 2.0

2/19/15:
-9am: Fc 12.5. Cc 2.0, Added 0.5 gal chlorine

2/20/15:
-11:30am: FC 11.5

He's about given up at this point (so I turned here for help), because we're about out of testing chemicals, nearly out the $80 in chlorine from Lowe's, and the pool still looks like this, which hasn't really improved at all in several days now:



Thank you!

 

[JasonLion]

Welcome to TFP!

What method did you use to measure the CYA level? And how confident are you of that reading?

Have you done an overnight FC loss test recently?

How has the filter pressure been behaving, and have you needed to clean the filter recently?

 

[kmaloney18]

It was with the TF100 kit. It was apparently double-checked the next day & the CYA was the same as my reading on the 9th.

Regarding the FC loss, he didn't do it specifically the way described on the site (he just looked it up.) Only an approximation using the day/night testing he did over the last week+ (he's going to try it tonight.)

The filter(s) was cleaned out/hosed down, etc., about 3 days ago. He's not aware of a change in filter behavior.

 

[Casey]

He needs to hit that pool hard (SLAM IT) until it turns the corner and the CC drops. I wouldn't hesitate for a moment to go to 20ppm FC just to get a better foot hold on that pool and just hold it for as long as it takes.

Brush! Brush! Brush!

Sweep! Sweep! Sweep!

Clean filter as needed.

TEST, SLAM, BRUSH, SWEEP... REPEAT.

 

[pwrstrk]

Welcome to TFP !
This can be fixed, but it's going to take time and effort on your part.
First take some time a reread the SLAM Process so you fully understand it. It HAS to be followed to the T or this can drag out for a long time. The big key to this is keeping the water at shock level for as long as possible. You need to test often in the beginning and bring your FC back to shock level when it falls below.
Stay on top of it and it will come around. Any questions don't hesitate to ask !

 

[chem geek]

large volumes of liquid chlorine &/or di or trichlor shock

For every 10 ppm FC added by Trichlor, it also increases CYA by 6 ppm.
For every 10 ppm FC added by Dichlor, it also increases CYA by 9 ppm.

If you do a recent CYA test and it's very high, then a partial drain/refill to reduce the CYA will have you use less chlorine in a SLAM to clear the pool. The SLAM level for a CYA of 90 ppm is 35 ppm, not the 14 ppm FC or so that has been maintained. 14 ppm FC with 90 ppm CYA is equivalent in active chlorine (hypochlorous acid) level to 4.7 ppm FC with 30 ppm CYA and is not a high enough level to kill algae quickly nor to kill it when it has formed clumps that make it slower to kill. This is why the SLAM level is set as high as it is -- in order to kill the algae substantially faster than it can grow even when it has started to clump. Your 14/90 ratio isn't even at half the SLAM level.

If you were to dilute the pool water to get the CYA level down to 50 ppm, then the SLAM level would be 20 ppm FC and you'd lose and use 40% less chlorine to clear the pool assuming most daily loss would be from sunlight.

 

[kimkats]

-Put in an order for new testing stuff.

-Find a better place to get chlorine unless you are SURE that the Lowes stuff was new.

-Read and reread the SLAM process and follow it to the letter!

-Take a picture looking down into the pool with something like the steps or a broom showing so you and we can see the color difference as it changes and clears.

It can be done BUT it will be a LOT of effort and time.

We can get you through it. Once you get on the other side you will never have to do it again IF you follow the TFP way!

HUGS and let us know if you have any questions!

Kim

 

[Patrick_B]

Hi Kmaloney! Welcome to the forum,

Lowes Chlorine often sits for months and months so it loses strength. It may be hard to believe right now, but this can be very easy and it's simply a matter of having enough FC in the water long enough to kill the Algae. Do let us know how you are testing and prepare to order more reagents. There have been many, many others with worse pools than yours and they've turned it around with what we teach here. I cannot stress enough to get the understanding of how FC behaves, especially with regard to the Cya level. If the Cya is this high or higher, that is undoubtedly part of your problem too. It's also one of the most common problems we see. This pool can be turned around quite easily I promise, so stick with us, and we'll help you learn how to do it.

 

[bigglesworth]

Regarding the Lowes chlorine... my experience is that either it is so old and degraded that it barely works, or it's not the 10% they advertise. I bought 2 cases of it once and it seems like I had to add twice the amounts that I normally add of the pool store bleach. You might have better luck with regular Clorox or the bleach (liquid chlorine... sorry) that the pool store sells.

Best of luck with your SLAM.

 

[pooldv]

we use 8.25% generic store brand concentrated bleach from the grocery store. Pool stuff at Lowe's is always really dusty.