Complicated situation regarding mustard algae

Apr 4, 2017
40
Saraland, AL
Pool Size
10600
Surface
Vinyl
Chlorine
Liquid Chlorine
I'll try to make this as short as possible while still giving all relevant information. Got my pool in early April and even with two birthday parties with way more kid in the pool than I've ever had before, I've had no issues with it or chemistry until now.
We recently had 9 days in a row of torrential rain which caused our garage to be flooded. I had to partially drain the pool 4 times due to overflow, to get the water level back below the skimmer. I am not sure what the overall amount of water loss from the pool was, but I kept monitoring my levels and maintaining the best I could. The rain finally stopped last Wednesday and my water was still sparkly blue, but had tons of sand, pollen, and small debris in it that my stock Intex cartridge filter couldn't handle alone. I vacuumed with my Catfish Blaster repeatedly and got enough sand and dirt to fill a kids sandbox - seriously - but I could still see sand. At this point, the water was becoming cloudy. Thursday morning, I went out to vacuum again. Got more sand and small fine particles that looked like nose hairs. Weird, I know. The more I vacuum, the more cloudy it got. By Friday morning, still sand on the bottom, but no more sand is coming out of the vacuum bag. When I vacuum or brush, the water becomes so cloudy that I can't see the bottom anymore.
Time to assume it's mustard algae because when I brush or or try to vacuum it, it "poofs" away. It was not slimy, and wasn't on the walls. Only in patches on the floor. I checked my levels, then dumped 3 lbs of shock into the pool that night. Saturday morning, water was so cloudy, and milky. Couldn't see floor at all. When you brush, it would stir up white stuff everywhere. Continued to brush and test. Sunday morning, looked a little better, but still very cloudy. Levels are all still good, except for chlorines, of course.
Monday, still cloudy, but when you scoop water out in a clear mason jar the water is perfectly clear!! I try to vacuum from the bottom of the pool to get some cloudy water, but it's clear too. Stumped, I go to the pool store for help. He says all my levels are right. Chlorine levels have drifted down a little, but are still high. Salt level is low, probably because I had to drain it so many times during the storms. Phosphate levels are extremely high. He said they've been flooded with calls from people in the area about the same issues. He sold me PhosFree, and some my husband all the parts we needed to finally repair the Hayward sand filter that the previous owner of our house left behind when they buried their inground pool last summer before listing the house for sale. It's now up and running, as can be seen in my sig. Added the amount of PhosFree he told me to, and woke up yesterday morning to a clear pool. I could even see the liner pattern. I could also see brown gunk on the floor. Of course, it poofs away and becomes super cloudy again when I try to brush. I have lots of bleach ready to perform a SLAM, but was waiting for my test kit to arrive so I can finally do things the way of the forum. Before, I was using test strips and the Clorox XtraBlue shock from walmart. Not ideal, but had to do what I could while I waited for my kit.

With the exception of the 5-10 minutes it took to swap from my Intex filter/pump to the Hayward sand filter, it's stayed on 24/7 since I dumped the shock in last week.

So now here's where I need your help: What order do I do everything in?
-- Do I SLAM first?
-- Do I add more PhosFree before or after SLAM? (he said I'd have to do it multiple times due to the high levels I had)
-- When do I add the salt?
-- How do I know when the algae is dead? Can I tell by looking at it?

My test kit came today (Taylor K20016) and here's the numbers: FC 5.4, CC 0.6, PH 7.6, TA 130, Stabilizer 80, Salt 2200
Photos of pool water in first comment.
 
Collage photo shows how water looks first thing in morning before being brushed, then after.
33c9e65e9ae9da94f99ff569c223b45b.jpg


Closeup of gunk.
2c06af4f7a4b28381dc7c8b0f231fd0e.jpg
 
Don't use the phosfree stuff it is a waste of your money. Add enough muriatic acid to bring the pH down to 7.2 and start the SLAM. According the the CYA chart you need to be at 31ppm. I would start using the 10ml sample size for the FAS-DPD chlorine test. Once you've passed the 3 criteria to end the SLAM you can worry about getting you SWG up and running.
 
At the pool store on Monday, my CYA level was 35. The only thing I've done since then (chemically) is add the PhosFree.
Could my CYA numbers really have changed that much in 2 days for no reason, or is it possible I did the test wrong? I can redo if I need to.
 
I would trust your CYA number before I would the pool store's. This is the test they most frequently get wrong.
 
My test kit came today (Taylor K20016) and here's the numbers: FC 5.4, CC 0.6, PH 7.6, TA 130, Stabilizer 80, Salt 2200

Hello and welcome to TFP! We will get things cleared up for you!

Great to hear you got a good test kit, you're going to need it.
It doesn't sound like you have mustard algae, but either way the fix for it is a SLAM.
Forget about the pool store results, trust yours. You can obviously see the difference in results.
High CYA will make the SLAM process a bit more difficult but since you have the SWG you're probably just deal with it. The needed FC will be higher but I don't think you want to change water to get CYA lower and then have to add it back in later.
So, The bad news, look at that Clorox XtraBlue shock and see if it had copper in it. How much of it did you use?
Going forward, no more solid chlorine products, liquid bleach only! Use the bleach to get your FC up to slam level based on your CYA of 80. You can forget about the salt and the SWG until after you finish the SLAM. The SWG cannot produce chlorine fast enough for the SLAM process so just turn it off to save it's life.
Please read the SLAM article and follow its instructions very closely, do not skip steps and do not add extra steps. You are done with the SLAM process when you meet all three criteria listed in the article. Please remember this is a process not a one time event.
Test and dose at least three times a day, more if you can for the first few days. Then you can taper off as you see the FC demand dropping.
When you do your testing, you only need to check for FC and CC, forget all all your tests.
Each day to take a photo just like the last one you posted to see your progress, towards the end your eyes might not see the difference but the photos will.
We will get you through this so you have a great looking pool!

Ask any questions you have...
 
So, The bad news, look at that Clorox XtraBlue shock and see if it had copper in it. How much of it did you use?
According to the bottle, 0.26% per bottle, and I used 3 bottles.

Going forward, no more solid chlorine products, liquid bleach only!
Absolutely! Much cheaper, much easier. I just wasn't prepared to try that way without the good test kit. Butt now, it's on!

Please read the SLAM article and follow its instructions very closely.
I have read it multiple times, and bookmarked it, as well as the page that shows the proper shock levels. I'm ready to do this, and do it right!

Test and dose at least three times a day, more if you can for the first few days.
Easy peasy. I'm a stay home mom, so time is on my side, for the most part. I've cancelled all daytime plans until this is taken care of. My kids are on my case about swimming and I'm ready to get in too.

Thank you so much for the detailed response. I don't have any other questions at the moment.
 
You've gotten good advice and will get this cleared up.

Now that you have a good large sand filter, you may want to get a hand suction vacuum and pole and vacuum through the sand filter. It should do a better job than the blaster.

- - - Updated - - -

P.S. I'm about a half an hour north of you.
 
You've gotten good advice and will get this cleared up.

Now that you have a good large sand filter, you may want to get a hand suction vacuum and pole and vacuum through the sand filter. It should do a better job than the blaster.

- - - Updated - - -

P.S. I'm about a half an hour north of you.

Yes, that's the next thing for sure.
How cool! There's never anyone around me.
 

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Photo from this morning. You can't tell here, but I could actually see the pattern of the vinyl
7f29d69ef4f96d5b9505ba1afe1e32cc.jpg


You can still some stuff on the floor.
f8894f9f5104b9d0279a070f99891c16.jpg


Testing, brushing, and adding more chlorine to keep it at shock level throughout the day.
When doing the CC test, if it doesn't turn pink at all, that means it's 0 CC, correct? If so, I've been at that since this morning. Now to pass the other two parts of the slam.
 
This morning's numbers before sun up:
FC 31 (it held!) and CC 0.5
Water is clear. I can see the liner all over.
fe6bbd53de121488012a1b86ccd2ed5c.jpg


It doesn't sound like you have mustard algae, but either way the fix for it is a SLAM.
I'm curious- What makes you think so? Because I'm beginning to wonder myself.
Although the water was finally clear this morning and I could see the liner everywhere, there were still a handful of spots on the floor. Before, they all poofed up when I got near them with the brush. Today, I got close, super close, even hovered over it with the brush, and it didn't poof until I actually touched it with the brush. Even then, it was a tiny poof, not a full-cloud that hovers in the water type of poof. I hope that makes sense.
I want to believe it's just pollen so we can finally swim, but there was no pollen on the pool railings or anything.

What should I do from here?
 
This morning's numbers before sun up:
FC 31 (it held!) and CC 0.5
Water is clear. I can see the liner all over.

I'm curious- What makes you think so? Because I'm beginning to wonder myself.
Although the water was finally clear this morning and I could see the liner everywhere, there were still a handful of spots on the floor. Before, they all poofed up when I got near them with the brush. Today, I got close, super close, even hovered over it with the brush, and it didn't poof until I actually touched it with the brush. Even then, it was a tiny poof, not a full-cloud that hovers in the water type of poof. I hope that makes sense.
I want to believe it's just pollen so we can finally swim, but there was no pollen on the pool railings or anything.

What should I do from here?

Great news. The SLAM is almost over!
When you say spots on the floor, are they just white poofs or still green?

Yeah I understood what you explained. I believe the white "poofed" material is just dead algae that has settled to the bottom. After brushing, your filter should get that out. That's another reason we recommend brushing, to stir up the water so your filter can do its job. If you have a hand vac attachment on a pole, you can use that to suck it up directly and be a bit more efficient at getting it out of the pool.

The Mustard Algae is typically found on the walls, in the shaded areas. Not so much on the floor. But if you want to be sure, just jack up the FC level to mustard algae levels for the last 24 hours. I don't think you need to, but the only down side is a day without swimming.

I'd say.. GO SWIMMING! you can see clearly to bottom, you have FC below SLAM level for your CYA and you deserve to enjoy your pool. That swimming will help stir things up and let your filter remove them.

When your are done swimming for the day bring FC back up to 31.

You can start to think about adding more salt if needed and get your SWG ready to go again.
 
Great news. The SLAM is almost over!
When you say spots on the floor, are they just white poofs or still green?

Yeah I understood what you explained. I believe the white "poofed" material is just dead algae that has settled to the bottom. After brushing, your filter should get that out. That's another reason we recommend brushing, to stir up the water so your filter can do its job. If you have a hand vac attachment on a pole, you can use that to suck it up directly and be a bit more efficient at getting it out of the pool.

The Mustard Algae is typically found on the walls, in the shaded areas. Not so much on the floor. But if you want to be sure, just jack up the FC level to mustard algae levels for the last 24 hours. I don't think you need to, but the only down side is a day without swimming.

The spots on the floor were a sandy color. When they poofed, they poof up a very light brownish color. As of 5 minutes ago, I looked at the water again. Still clear. No spots to be found. Some tiny white stuff floating around but that's it. We are in the way to the pool store now to buy a vacuum hose.

The stuff, whatever it was, was never on the walls. Only in random spots on the floor. That's what didn't make sense. I just figured it if were pollen, I would have seen it on the pool rails and other places. In the southernmost part of Alabama where I live, we always have pollen when it's warm. Going to the weather website and typing in my zip code, at the top of the page is a "High Pollen Alert" banner. So who knows.
We'll probably swim today and just do like you said, bring it back to 31 afterwards and then bump it to MA shock level just in case. I don't want to have to deal with this again. That's for sure.
 
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