Water not holding chlorine.

[maxthesilent]

I am in Las Vegas and I emptied and refilled the pool on March 25. Once filled, I added in 1 gallon of conditioner and the levels were as follows:
FC 0
PH 8
TA 130
CH 220
CYA 20
Water temp 62
I added in 69oz of liquid chlorine and 25oz of acid. The next day, levels came in at:
FC .6
PH 7.6
TA 130
CH 220
CYA 20
Water temp 65
A week later I added a second gallon of conditioner.

We had a lot of wind in Vegas this spring, as well as a ton of concrete work done on the pool deck and a lot of rock moved around causing even more dust and sand to wind up in the pool. Due to this the filters were cleaned again on April 29. Water would get cloudy every few days so I used some clarifier and powdered shock, which cleared it up. As we went into May, I wasn't getting chlorine to hold, then I started getting yellow alge. I had Leslie's run the numbers and they were close to mine, but they were confused as to why the hardness was around 250. The kid that tested it was mystified by it all and suggested putting 15lbs of hardness up in it, followed by 2lbs of alge out, followed by 6lbs of shock over two days. This got rid of the alge and when I ran the numbers last week they came in:
FC .6
PH 7.6
TA 110
CH 330
CYA 20
Water temp 81
These numbers were about the same yesterday, and I added in 64oz of chlorine and 22oz of acid.

The CYA number may be lower as I'm still seeing the black dot in the test vial when it's full of tested water. PH has been fluctuating between 7-8 from test to test. Leslie's didn't think I needed a third gallon of conditioner, but I'm thinking that may be what is needed to get it to hold. I am going to clean the filters again this week as part of the post alge treatment. The water looks perfectly clear now, but we also haven't had as much wind blowing pollen and dust into it either.

I'd appreciate any thoughts on where I'm off and appreciate how much I've learned on the site!

Pat

 

[YippeeSkippy]

Is your pool in full sun, shaded or what? Yellow algae is usually only found on shaded areas of the pool.

Did you rinse out the jugs of liquid conditioner to get the thick sludge out of the bottom and into your pool?
Being that you're in "Lost Wages" your heat and sun dictates a higher level of CYA..... perhaps even up to 50ppm?
For an 18,000 gallon pool, each rinsed out full gallon of Liquid Conditioner will raise your CYA by 20ppm.

You are keeping your Free Chlorine (FC) entirely too low, and adding all those granular products would have also raised your CYA a bit too. What do you use *daily* to add chlorine? Chlorine is a consumable item, and will get used up by the sun and contaminates/ bather load. It *must* be replenished on a daily basis. Ideally either by using a Salt Water Chlorine Generator (SWG) or Liquid Chlorine. Pucks and granular products will add chlorine but also unwanted other chemicals too.

The CYA in your pool helps "hold on" to FC so that it is there and available to kill the cooties. The higher your CYA level is, the higher your FC needs to be.
See chart --> FC/CYA Levels

A calcium hardness level of 250 is totally believable. And will go up in short order when water evaporates from the pool but the calcium remains.

A product called "Algae Out" may be a problem. Was it perhaps called "Yellow Out"? That stuff is aluminum and will chew thru your chlorine.

Have you obtained your own TFP endorsed test kit yet?? Either the TF-Pro from www.tftestkits.net or K-2006C from Amazon.

Please get back to us with more info-

Maddie

 

[maxthesilent]

Hi, Maddie, thanks for the reply.
The pool gets sun for about 10 hours per day with the two algae spots getting full sun about half that time.
I think I rinsed out the jugs, but not 100% sure.
I have been trying to just get the water to hold chlorine, so it's not a matter of me keeping it low, it just won't hold.
I cleaned the filters again on Wednesday and added half a gallon of liquid chlorine. Yesterday morning it still wasn't showing any chlorine (or CYA) so I added another gallon, but as of yesterday afternoon it still was not showing any chlorine.
Yes, the algae killer I used was Yellow Out.
I am using the Taylor kit.
Last nights tests showed the following:
FC 0
PH 7.8
TA 110
CH 360
CYA 0
Temp 81
The Pool Math app is recommending just over three gallons of "stabilizer" to raise the CYA. Would this be the same as the conditioner I've already used? I've never had a water change require more than two gallons.

 

[Texas Splash]

Max, as a Vegas native myself I know the area well. Windy can be an understatement at times. In any case, it appears you still have algae or something else eating the chlorine and apparently the CYA. But let's step-back and focus on the following to try and get your water back on track:
1 - Add nothing to the water from this point forward except for liquid chlorine. That is your pool's best friend.
2 - For reference purposes, our pools are almost the same size, so one gallon of 10% chlorine should increase your FC by about 5 ppm.
3 - For the CYA test, did you do it outside under the sun. It's a bit odd to see your CYA zero after 2 gallons which "should" have taken it closer 40 ppm. So before we go any further, the CYA is very important. Please check the note below to see if that is how you did your CYA test.

CYA Testing:
Proper lighting is critical for the CYA test, so you want to test for CYA outside on a bright sunny day. Use the mixing bottle to gently mix the required amounts of pool water and R-0013 reagent, let sit for 30 seconds, then gently mix again. Recommend standing outside with your back to the sun and the view tube in the shade of your body at waist level. Then, begin squirting the mixed solution into the skinny tube. Watch the black dot until it completely disappears. Once it disappears, record the CYA reading. To help the eyes and prevent staring at the dot, some people find it better to pour & view in stages. Pour some solution into the viewing tube, look away, then look back again for the dot. Repeat as necessary until you feel the dot is gone. After the first CYA test, you can pour the mixed solution from the skinny view tube back to the mixing bottle, gently shake, and do the same test a second, third, or fourth time to instill consistency in your technique, become more comfortable with the testing, and validate your own CYA reading. Finally, if you still doubt your own reading, have a friend do the test with you and compare results.

 

[maxthesilent]

I was at Leslies getting some filter spray and the guy there thought the chlorine was in a death match with the yellow out. I even did a very light acid wash of the filter chamber.
So how often am I adding chlorine? A gallon per day until it shows up?
I've done the CYA pretty close to the above and still have not seen anything.

 

[Texas Splash]

I've done the CYA pretty close to the above and still have not seen anything.

In that case, I suspect you have a bit of a pool cocktail going on there based on the low FC, CYA that apparently was consumed, and other products added to the water recommended by the local pool store. I would recommend doing the following:
1. Make sure pH is lowered to about 7.2 with muriatic acid.
2. Use liquid chlorine (have lots of it ready and on-hand) to increase the FC to "10", then test again in 10 minutes. If the FC holds between 5-10 ppm for 10 minutes, go to the next step. However, if the FC crashes to 4 or lower, increase it right away back to 10 and re-test in another 10 minutes. Continue this 10-min drill until you clearly know the FC is showing signs of holding for 10 minutes.
3. Once the FC is holding, THEN you can add stabilizer/conditioner for a CYA goal of "30". At the same time, increase the FC to "12" which is your new SLAM Process FC level. It is important from this point forward you test and maintain that FC of 12 as much as needed at intervals to ensure the FC remains at or very close to 12. Continue this along with all the other tasks noted on the SLAM Process page until you pass all 3 SLAM criteria.

Once in SLAM mode, focus on the FC testing. No need to test pH, TA, or CH until after the SLAM is completed. If you have any questions, let us know.

 

[an1vrsy]

Where are you getting your liquid chlorine at? Have you checked the date code (freshness) before purchase? Unless you have a SWG you have to add chlorine daily.

I would add a gallon ensure it is well mixed then test in 15 minutes.

 

[an1vrsy]

Max, Pat has you covered, follow his instructions. Are you near Windmill and Eastern? Fresh Pool Supply is over there and last I checked there prices for 12.5% chlorine was great. I have a SWG so I don’t drive over there very often.

 

[maxthesilent]

Texas Splash: Thanks, will work on this tomorrow while I'm off.
an1vrsy: I've been buying it at Lowe's since they've had a pretty good price on it. Hadn't even bothered to check the dates since they seem to go through it pretty quick. I'm at Windmill and GVP, so I usually hit up that Leslies on Eastern. I'll check out FPS.
Thanks for the help, guys, will report back tomorrow!
Pat

 

[YippeeSkippy]

Blame a lot of this on that Yellow Out chem you added. It is made of Aluminum which just chews thru chlorine. But the good news is that the solution to that is....MORE CHLORINE!
You'll get there. Have faith. Trust in your own test results.

Maddie

 

[curtisb]

Max, Pat has you covered, follow his instructions. Are you near Windmill and Eastern? Fresh Pool Supply is over there and last I checked there prices for 12.5% chlorine was great. I have a SWG so I don’t drive over there very often.

I live in North Vegas I I get Walmart chlorine for $4.63 per gallon, and no expired. How much do you guys get yours for? Wondering if its worth the drive? Well, not really probably cost an arm and a leg to get there to save a couple fingers...

Curt

 

[an1vrsy]

I wouldn’t drive that far to save 50¢ a gallon for chlorine. I don’t even remember the price. So, Pool essentials from Walmart is good at $4.63. I only mentioned that pool store because he was close and it wasn’t franchise Leslie’s.