Help!! Woke up to algae in pool

Aug 1, 2011
25
I have an inground 18by 36 pool with roman ends. 30000 gallons of water. vinyl liner, cartridge filter, pool pilot swg 1 3/4 pump. No heater. I woke up today to some algae on the bottom and on the walls.

My salt level was 2500 so i added 120 popunds of salt to bring it up according to the package 480 ppm so it should be 2980. The slat level is tested at 3300. i got morton pool slat from walmart. First time I used there salt I always used pool store salt. could that salt be bad?

ph 7.6
ta 70
ch 90
fc 2
cya was at 25 i added on monday 3 pounds of cya should bring it to 35. i havent tested because they say cya still can take a week to totally dissolve.
I orderd the tf100 kit. i am using a walmart kit that tests ch ta cya and ph and fc. it worked well for me till i added the salt adn cya..

will adding 2 gallons of liquid shock be okay to start to kill the algae? willthis also raise my cya up? i read that adding shock will raise it. i dont want it raised much more or have it go over 100ppm. it is a slight algae and only in certain areas of the pool. i think my numbers seem to be okay. also for a swg i was told to get a certain type of chlorine i think it was hypo chloride or something like that. please help me out soon.. like i said i thought my nimbers were pretty good so where did this algae come from????
 
george171 said:
First time I used there salt I always used pool store salt. could that salt be bad?
I would guess you salt is fine. Are you positive you pool is 30000 gallons? I would have guessed (without knowing you bottom dimensions) that it is more like 25000 gallons. In addition, most salt tests have a +/- 400 ppm accuracy. How did you test for salt? Either way, 3300 is not a problem.

george171 said:
will adding 2 gallons of liquid shock be okay to start to kill the algae?
You need to follow the shocking process.

george171 said:
willthis also raise my cya up?
Nope, "liquid shock" is really just liquid chlorine with sodium hypochlorite at 10% or 12.5% (usually). Does not affect cya at all. It is a great choice for doing the shocking process. We recommend not using your swg during the shocking process and just using bleach/liquid chlorine.
george171 said:
like i said i thought my nimbers were pretty good so where did this algae come from????
If your pool has dropped below 2 ppm FC (your normal minimum for 25 ppm cya)at some point, that could cause it. With cya as low as that, your swg may not be keeping it above 2 ppm as the sun comes off the pool.
 
I just went out and rechecked the numbers. (hth test kit from walmart) I checked thew salt with a strip that turns from brown to white. they seem to be pretty accutrate.

ta is 70
ch is 130
ph is 7.6
fc is in the box 1/2 ( i used both test strips and the usual kit where you fill the tubes with water and add 5 drops of oto solution. and get the same result-- the color sqaure on the test strip bottle is 1/2 and the tube color matching is at the 1/2 panel)
cya seems to be between 50 and 60

On the cya I am using a squueze bottle filled to a 7ml line and then addeing a cya reagent to the 14ml line, mixing it for 30 seconds and then squeezing the solution into a smale tube with a black dot at the bottom, when it gets to the 60 line i can barely see the balck dot at the bottom and then when i fill it to the 50 line it is completely gone, so i am taking the reading to be somewhere between 50 and 60. again i added 3 pounds of hth stabiler to the skimmer on monday so i am sure it might still go up a little but probably no where near 100. which i know i dont want to be above 100.

how should i start shocking being i dont have the tf100 kit yet? and can the kids swim in the pool with the high level of chlorine?? 6 and 3 year old. i am alos having a pool party this sunday. DO you think the pool will be crystal clear by then???
 
For sure add bleach to get up to shock level, 16 or so. Brush the heck out of it. The OTO test should turn orange. Study that color and try to keep it looking like that by adding bleach as needed. It's far from exact, but you don't want the algae bloom to get worse.

I'd keep the kids out while it's that high. It probably won't hurt them, but I wouldn't risk it myself.

You're going to have to jump on it now if you want it clear by the weekend.
 
@ Richard or anyone else, If my chlorine level is at 1/2 about how many gallons of liquid chlorine will i need to get the level up to the 16 or so that is reccomeended for shocking for a 30000 pool. And someone asked about the gallonage, thats what the pool company has the gallons listed at that built the pool. the pool like i siad is a recatangle 18 by 36 with two roman ends that add 4 feet to both sides. the shallow end is 3 1/2 feet deep and the deep end is 8 feet deep. i am guessing the 30000 is accurate. also how do i shut the swg down and will that high level of chlorine go down if i have the swg on, will it lose the chlorine?? i mean if the swg raises it to 2/3 each day and it has say 16 in it from shocking will it eventaullyt lose the 16 numbe and start coming down??
 
george171 said:
@ Richard or anyone else, If my chlorine level is at 1/2 about how many gallons of liquid chlorine will i need to get the level up to the 16 or so that is reccomeended for shocking for a 30000 pool. And someone asked about the gallonage, thats what the pool company has the gallons listed at that built the pool. the pool like i siad is a recatangle 18 by 36 with two roman ends that add 4 feet to both sides. the shallow end is 3 1/2 feet deep and the deep end is 8 feet deep. i am guessing the 30000 is accurate. also how do i shut the swg down and will that high level of chlorine go down if i have the swg on, will it lose the chlorine?? i mean if the swg raises it to 2/3 each day and it has say 16 in it from shocking will it eventaullyt lose the 16 numbe and start coming down??
The Pool Calculator will do the math for you. As soon as you add bleach to get to 16 it's going to start dropping. So you'll need to add more again and again and again until it clears up.

You need to re-read pool school.
 
Okay so the pool is now much better. I held the chlorine shock level up there and it is slowly coming dfown. It is now showing a dark yellow color and not orange. Two questions.

1- When can the kids go in the pool.
2- I now have spots on the bottom of the pool that look like sand but when I touch them they cloud up ands go away.

Is this stuff the organic material that the shock has killed? Do I have to brush the pool again and kick it up? Wont this jjust dissipate it for a bit and then it will eventually settle again. Or should I vacuum it up? I dont have a regualr vacuum. I have a polaris 380 will this do the trick? Or do i have to go out and get a regualr vacuum and hose?

Lastly, 2 years ago, the pool store guy told me that this stuff on the bottom of the pool is the dead phosphates. Is that true? Please le t me know soon. My pool party is tomorrow afternoon. Thanks for all the great help here.
 
School bus yellow....hmmmm that's a new one.
However I don't think you have completed the shock process correctly, you have to follow it step for step and I don't think you have met the 3 criteria that says you are done shocking your pool.......Mike
 
Why would you say I havent completed the shock process?? If you are taking when I say the level is coming down, I meant that the chlorine level is coming down. It should not stay at 16 all the time right.. It has to come down to my range of 3-4ppm. or else it would always be at 16 right??
 

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You are supposed to maintain shock level FC until:
1. CC are not more than 0.5ppm
2. You pass the OCLT
3. Your water is clear

Have you passed those tests?

Posted from my Droid with Tapatalk ... sorry if my response is short ;)
 
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