Dead algae? At my wits’ end!!

Colleen0904

Member
May 25, 2021
11
Rincon, Georgia
Hello everyone! I’m a new pool owner as of this summer and this is my first time posting here. We have a 20x48 intex ultraframe pool with the basic filter it came with. We were doing great at the beginning of summer and then after tropical storm Elsa came and dumped a ton of rain on us, the chemical levels in the pool went wonky. Ever since, we have not been able to get back on track. We had algae in the pool, and we have tried shocking to get rid of it, as well as algaecide. Daily brushing and vacuuming haven’t seemed to help. Now we have these clusters of sediment on the pool floor. They’re easily stirred up, but if I try to vacuum them out, they just turn into little clouds and make the water cloudy, before settling (mostly into the creases of the liner) again. I’m assuming it’s dead algae, but how do I remove it if vacuuming doesn’t work? We scrubbed, vacuumed, and shocked the pool last night, and this morning the stuff is still there. My filter has been running nonstop. Also, the entire time, we have had HTH chlorine tabs in a floating dispenser. Yet the chlorine always reads 0, except for this morning after the shock and running the filter overnight, it was at 6.5 ppm FC.
I have the TF-100 test kit that was recommended on here, and these are my test results from this morning:
FC: 6.5
PH: 7.2
TA: 90
CH: 125
CYA: minimal, if any. I added some chlorine stabilizer at the beginning of the season and it was always within the acceptable range. At the time, we were using liquid chlorine (10% sodium hypochlorite) But after we had a TON of rain, the CYA seemed to be nonexistent. Of course I haven’t been able to find any in stock anywhere right now, either. I’m going to check a few stores today and hopefully find some stabilizer because it seems like my chlorine disappears before it can do anything! And the chlorine tabs that we have been using (that was the only chlorine I could find in stock anywhere at the time so we switched from the liquid chlorine to the tabs) that say they have stabilizer already built in, seem to be doing nothing as well because the chlorine levels are normally at 0.
My family was hoping to be able to use our pool over this long weekend. Is there any chance of that? How do I proceed from here?
-Do I add CYA/stabilizer first? (Assuming that I can find any in stock)
- Do I shock the pool again? add flocculant or clarifier or anything?!

Sorry for the long post, but I’m so frustrated and completely stumped. I’ll try to attach photos as well in case that’s helpful!
 

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Do not add floc or clarifiers!!! It will make your pool worse. Ask me how I know.

I would do an OCLT. Overnight Chlorine Loss Test This will give you a sense of whether you need to SLAM or not. You don't list your CC. You should be able to do that test with your kit. Will give us some insight on Algae.

Yes, try to find some CYA. Make sure it is 90-100% CYA and doesn't contain the name BLUE.

I would recommend downloading PoolMath to your smart phone if you have one, will really help you with correct additions and you can share your logs here to help us diagnose.

For now, add 5ppm of Chlorine daily while you do OCLT to figure out next steps. 6% bleach would be 80 ounces a day, 10% would be about 51 oz. a day and 12.5% would be about 41 oz.

Fill out your signature and when you get pool math, enter your pool size. It will help you with daily recommendations. Don't do anything else (but add chlorine/CYA) until you do OCLT and test your CC.

It it is ALGAE, then you will need to do slam. Read up so you understand, in the case you need to perform: SLAM Process
 
Do not add floc or clarifiers!!! It will make your pool worse. Ask me how I know.

I would do an OCLT. Overnight Chlorine Loss Test This will give you a sense of whether you need to SLAM or not. You don't list your CC. You should be able to do that test with your kit. Will give us some insight on Algae.

Yes, try to find some CYA. Make sure it is 90-100% CYA and doesn't contain the name BLUE.

I would recommend downloading PoolMath to your smart phone if you have one, will really help you with correct additions and you can share your logs here to help us diagnose.

For now, add 5ppm of Chlorine daily while you do OCLT to figure out next steps. 6% bleach would be 80 ounces a day, 10% would be about 51 oz. a day and 12.5% would be about 41 oz.

Fill out your signature and when you get pool math, enter your pool size. It will help you with daily recommendations. Don't do anything else (but add chlorine/CYA) until you do OCLT and test your CC.

It it is ALGAE, then you will need to do slam. Read up so you understand, in the case you need to perform: SLAM Process
Thanks for the reply! My CC is 1. I do have the pool math app, just not sure how to make it so I can share my logs. I’m not the best with technology 🤣
I will venture out to the stores and try to find CYA. This shortage of pool chemicals is really making it hard to maintain the pool! I’ll also read up on the SLAM process as well as the OCLT. I’m assuming ai will have to SLAM again if my CC is 1?
 
Thanks for the reply! My CC is 1. I do have the pool math app, just not sure how to make it so I can share my logs. I’m not the best with technology 🤣
I will venture out to the stores and try to find CYA. This shortage of pool chemicals is really making it hard to maintain the pool! I’ll also read up on the SLAM process as well as the OCLT. I’m assuming ai will have to SLAM again if my CC is 1?
Yes, with CC at 1, you have some organics, I would do the OCLT. Adjust your FC to whatever your target is, and run the pool pump for 30-45 minutes. THEN, AFTER SUNSET, test FC. BEFORE SUNRISE, test FC. If they are further apart than 1, then you will need to SLAM.
 
Thank you!! I actually was able to find some chlorine stabilizer so I will be adding that today. I’m going to backwash the filter first, like the directions say. Can I just leave the floating chlorine tab feeder in there during the SLAM and overnight chlorine loss test? There is a little less than 1 full tablet left in it, and the directions say not to remove the chlorine feeder from the water for more than 5 minutes if there is any tablet/tablet residue left in there.
 
Take the floater OUT and get rid of it. Hold your breath, put it in a plastic bag and tie it up. If you leave the floater in the pool it will add chlorine while it is in there and the OCLT will be invalid. The OCLT is to see how much FC you lose that is not due to the sun (why you check after sunset and before sunrise). If the loss is greater than 1, you have an organic (algae) problem and will need to slam.

We do not recommend using pucks except for vacation. It is really hard to dose FC correctly, and it continually adds CYA. If you want to keep the floater for vacation, hold your breath longer and just throw that puck out and rinse off the floater.

More Reading:
ABCs of Pool Water Chemistry
Recommended Levels
FC/CYA Levels
 
Okay I’m back. We added the stabilizer yesterday and did the OCLT. The FC was at 3 both times, so we didn’t lose any chlorine overnight. What would the next step be?
1) What was your CC?
2) What does the pool water look like?
3) How much stabilizer did you add?
4) What type of vacuum do you have?

Answer 1-4 and we can get you next steps!
 
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I do have the pool math app, just not sure how to make it so I can share my logs. I’m not the best with technology 🤣
Go to summary (page with all your current results). Touch the gear in the upper right hand corner.

Scroll all the way to the bottom and enable "Link from TroubleFreePool.com user profile"

Then we will see them!
 

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1) What was your CC?
2) What does the pool water look like?
3) How much stabilizer did you add?
4) What type of vacuum do you have?

Answer 1-4 and we can get you next steps!
CC was .5
The water looks a lot better to me. There’s a few bugs here and there but overall the algae seems to be gone.
I added 3 lbs of stabilizer. When I tested it today the CYA level was about 45 ppm.
As for the vacuum, we only have a small one. It’s one that attaches to the garden hose and uses that to suck the debris into a net, so we don’t use the filter at all. From my understanding, the Intex pump/filters aren’t strong enough to be able to use a regular vacuum. Eventually we hope to upgrade the filtration, but for now we have put enough money into our “pandemic pool”. Lol. I’ll attach a photo of the vacuum as well. It’s not the greatest but it gets big stuff up at least.
 

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GREAT!!! You passed slam.

I would simply resign myself to allow the filter to do what it can to filter out the remaining dead algae. Vacuum isn't going to work. Go SWIM! that will mix the water and allow filter to do it's work. Remember to backwash when your filter pressure rises 25% from it's clean pressure.

With CYA, it is either 40, or 50. It is a log scale so you can't read in between. If you can see dot at 40 but not at 50, call it 50.

So with CYA of 50, increase your FC to 8 and keep it there. It is the high end of the recommended range, but will give you some protection from loss. Do it now. Add whatever liquid chlorine you need to get it up to 8. Don't wait, do it now.

You can test a couple times a day and add chlorine if necessary to keep it at 8 until you start to learn how much Chlorine your pool uses.

Don't sweat the stuff on bottom it will come out as you stir it up and filter. Go Swim. Keep your FC at 8. ENJOY THE LONG WEEKEND!!!
 
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so we don’t use the filter at all.
Wait...is your pump filter turned off???

Ok, I looked at the manual for your pool. No skimmer, just two ports, in and out. I would just keep running your pump/filter. It should take the stuff out of the pool as you swim and stir it up.
 
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@Colleen0904 Checking your logs, I'm concerned about your chlorine. At a CYA of 50, you must never let it get below 4. Even Flirting with 4, and you are dancing with algae. CHECK OUT: FC/CYA Levels. You need to keep it between 6 & 8. I recommend just target and keep close to 8. You won't feel it or smell it. It will cause no damage. It will protect you from algae.

You should have added 53 oz. (half a gallon if you don't want to measure) when your FC was 1.5 today (Assuming you have 12.5% LC) You should get it to 8 and keep it there until you know how your pool consumes FC. You may want to test a couple times a day until you get a feel for it. How did you come up with 30 oz.?
 
Wait...is your pump filter turned off???

Ok, I looked at the manual for your pool. No skimmer, just two ports, in and out. I would just keep running your pump/filter. It should take the stuff out of the pool as you swim and stir it up.
Noooo the filter has been running nonstop during the whole process. It runs for 12 hrs, and then shuts off automatically. So we go back out every 12 hours and turn it back on.
I added enough chlorine, according to the pool math app, to get to 6 ppm FC, which is what the app said to do. I had the kids in the pool for about 30 mins before we took a dinner break. I’ll retest and see what the levels are. I was just following the recommendation on the app.
 
Noooo the filter has been running nonstop during the whole process. It runs for 12 hrs, and then shuts off automatically. So we go back out every 12 hours and turn it back on.
I added enough chlorine, according to the pool math app, to get to 6 ppm FC, which is what the app said to do. I had the kids in the pool for about 30 mins before we took a dinner break. I’ll retest and see what the levels are. I was just following the recommendation on the app.
Well we learned today that your swimming consumed a bunch of chlorine and you got below 4 (1.5). You started at 6. If you keep at 8-9, you would only have gotten to 3.5 to 4. Also learned that you might want to add a bit before and after swimming so you NEVER get close to 4!

for now until you learn more, keep it 8-9, even 10 will not hurt. You can lower your target when you learn how your pool behaves.
 
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So if I want it that high then I have to do the test for FC every single time? Not just the basic drop test that tells me chlorine levels up to 5 ppm right? We have always just used that part of the test kit except for once every so often when the levels get weird. The LC we use is 10%. I guess maybe I’m confused because what is in the test kit instructions is so different than what the pool math app is saying. I just retested the water and updated the results. It was only at 3.5 ppm, so I guess after the kids get out I will add more chlorine.
 
Did you configure pool and volume in pool math. I configured your pool from your sig, I get different results.

look at jug and give me date code on bleach.
 

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