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Hi! I have a 15,000 vinyl lined in ground pool with a SWG. Yesterday at 4pm the water was real green (couldnt see bottom).
Cl 4.0
Ph 7.8
Alk 80
CYA 30
I added 50oz of stabilizer and 8 gallons of bleach.
This morning the water is light green, still cant see the bottom.
cl off charts, orange color
Ph 7.8
Alk 70
CYA 55
Should I just wait or should I add more bleach since I don't have an accurate reading on my Chlorine levels?
Thank you so much for any advice! Love the site!
you need a FAS-DPD Cl test kit...
but in the meantime, you can dilute your pool water with distilled water and repeat the test
I've used a measuring cup in the past- get 3 cups distilled water, 1 cup pool water, test for Cl and multiply by 4...
I wouldn't add anymore stabilizer
Keep your Cl at shock levels until clear, and run filter 24/7 throughout!
Keep us posted, we'll help you get it clear; it'll just take some time!
Ouch!
Why did you add the CYA? It doesn't aid in getting rid of algae! But we can work around that.
OK, OK. It's not that bad. We've see much MUCH worse. But don't add anything more except what we indicate below. Don't "try" algaecides, clarifiers, phosphate removers, etc. There's not quick and easy way and they will make the problem worse.
You have to kill the algae and that means chlorine.
Remember the old adage: "When you are up to your (waist) in alligators it's hard to remember that the objective was to drain the swamp." So let's stick to getting out of the swamp! :)
I'm guessing you have an OTO test kit that goes to 5ppm max for chlorine. If you dilute the pool water 1:1 with distilled water (steam distilled, nothing else--your supermarket or chain drug store has it cheap) you double the range of your tester--if it goes to 5, now it goes to 10. Search our site for the Shot Glass Method. If you use 2 parts distilled to 1 part pool, it now goes to 15.
This will tide you over but you really need to get a proper FAS-DPD test kit. We recommend the Taylor K2006 or K2006C kits (not the K2005). It's online at TaylorTechnologies.com. There are some other source, but apparently the one that helps PoolForum isn't working right now. Or you can get it online from Leslies as the "Chlorine FAS-DPD Service Test Kit". It's the same as the Taylor, only re-badged by Leslies. Same thing, though, even uses Taylor chemicals. You won't find an FAS-DPD test in a pool store, only online.
For now, don't worry about CYA or Alk. Only pH and Chlorine levels matter. I suspect your CYA level is going to keep rising, meaning you will need higher and higher chlorine levels.
First: Get your pH down. You can use either Muriatic acid (Be VERY careful, wear gloves and goggles) or dry acid. I prefer to always mix either first into 5 gallon bucket of water (ALWAYS add the acid to the water, not the other way around).
You want to lower your pH to 7.0 to 7.6, no lower or your liner may be weakened, no higher or you chlorine won't be as effective. So do it GRADUALLY. If you use Muriatic, add a cup to the 5 gal bucket of water (pool water's fine) and put it in the pool. After an hour, test the pH. Repeat until the pH is in range. For dry acid, use no more than half of what the container recommends to lower your pH as much as they say. (As you pH comes down, you will notice your Alk comes down as well. FOR NOW IGNORE THAT!)
Next, you need lots of chlorine. Bleach is best. With your CYA at 55 ppm and almost certainly rising I would aim for the chlorine shock level recommended for CYA between 60 and 90ppm--a Free Chlorine value of 20ppm. That's 5 gallons of 6% bleach to start. Expect to add that much 3x every day--morning, noon and night. If your CYA goes past 100, you'll have to add at least another gallon + 1 quart, to reach a shock value of 25ppm. That's what it's going to take to kill the algae and clear your pool. If you prefer to use Liquid Chlorine which is 12.5 strength (just like bleach, only twice as strong), you'll need almost 2.5 gallons to reach 20ppm, or 3 gallons to achieve 25ppm.
It may take several days to do this but it may go faster. Consistency is the key.
Meanwhile, follow the basic rules of running your pump 24/7, vacuum to waste each day, and brush your pool each day.
It's not complicated, but it does require P.O.P.---Pool Owner Patience, as Ben likes to say.
Carl
Thanks CarlD!
I just figured I could kill all the algae, wait a couple hours, and then try and reach CYA of 55 by adding stabilizer. The pool calculatorc ame up with the amount of stabilizer. I was too impatient... I will be following your advice and will post my results. Muriatic acid and then lots of bleach.
Thanks again!
Don't retest your cya for about a week to give it time to totally dissolve. Otherwise, you just waste your testing reagents. How did you add it? To the skimmer, in a sock hung in front of a jet, or broadcast across the pool?
I added the stabilizer directly into the skimmer box. It was still reading 55 but I will wait a week. The water is no cloudy but I can seee the bottom! Almost there...
Keep your chlorine up and your filter running. Watch your filter pressure, because it will rise as the dead algae starts to filter out. Unfortunately, when you backwash your filter you will wash out the remainder of the CYA you added, so don't backwash it til you have to, and I wouldn't test for CYA again until you do, so you'll know where your starting point it when you add more.
Janet
Ok. Test results today: Cl 10, Ph is 6.6 or maybe lower (test kit didnt go that low), Al 70 and CYA is 20. We got a ton of rain this week and I have been rinsing the filters due to all of the dead algae. Should I still wait for the cholrine to drop to add stabilizer? When should I add soda ash for my Ph? Al? Please help.
Thanks again!
If you haven't added any stabilizer, go ahead.
Also, add a box of borax a day, till your pH is above 7. (Low readings of pH, with highish chlorine are more likely to be right than high ones.)
Ben
FYI -- the reason Ben suggested you use Borax to raise pH instead of soda ash is that soda ash affects pH and alk whereas, Borax will mostly affect pH and your alk is fine where it is.
Thanks! I added a box of borax and 40oz of stabilizer. Tested the Ph and it didn't move (still below the testing kit colors) from 6.6 or lower. Can I add more Borax or should I wait till the morning?
I would wait until there's been about 4 hours since your last Borax addition. Retest for pH, and if it's still less than 7.0, add another box, slowly. Looks like your pH is much lower than what the test can register, so it can take quite a few boxes of Borax to get back where you need to be.
Janet
Retested this morning. Cl 12, Ph 6.6 or lower, CYA 30. Added another box of Borax as the first box didn't seem to do anything. The label on the stabilizer said to adjust your Ph to the correct level before adding. I already had added 42oz to get my CYA level to 40. I was going to just wait a while before adding anymore stabilizer to see if it will continue to rise. Once again, we were hit with a lot of thunderstorms that dropped a lot more rain. Any suggestions?
Thanks again for all of your help!
Don't add any more stabilizer at this point. Keep adding Borax a box at a time until the pH starts to move. Wait a couple of hours, retest and redose. You need to get that pH above 7.0 ASAP.
ok.
ph is now 7.4 and Cl is 5.0. The pump has been running 24/7. Should I stop running it for so long and turn on the SWG?
Thanks!
Latest test results: Cl 3.0, Ph 7.6, Al 70 and CYA is at 35. Pool is crystal clear. I turned the pump down to about 6 hours and turned the SWG to 15%? What should I do next? Add CYA, baking soda? Thanks again for all of the help!
I'm quick posting, b4 I have to go out again, so I haven't reread the thread.
+ Basically, don't mess with calcium or alkalinity unless you have a concrete pool. (Don't mess with alkalinity till you've fixed calcium, if you do.)
+ Don't turn your SWCG on till you have an acceptable salt level.
+ If your SWCG is not oversized, it may not be able to deliver enough chlorine at 15% and 6 hours -- remember that it is off (or should be!) when the pump is off.
+ Read the "Best Guess . . . " page (link below) and set your chlorine level using it.
Ben
I understand not caring about calcium for a vinyl lined pool (wish I would have found this site years ago and saved hundreds...) but I don't need to care about alkalinity as well? It is 70 now and the ph 7.6, Cl 2.0 and CLY is 35. Thanks
It's not so much that you don't need to care about it at all. It's just that it's usually not as big a deal as pool stores say. If your pH is OK and stable, and you don't have a concrete pool or heater . . . your alkalinity is probably OK where it is.
Ben