Help needed. SLAM started. Possible yellow algae?

[stoles]

Hey everyone. This is our first season with an open pool. It was installed last fall and basically looked like a toxic waste pit before a few cleanings and the installer closing it. It was not well balanced at closing.
We had it opened by another company in March. It was a bit green, but mostly cleared up after a few days of their cleaning. We just had what seemed like dead algae settling and we kept vacuuming. Eventually that stopped. Now it seems pretty clean except we keep getting a film that looks like dust on the walls in certain areas. The dust has a green/yellow color, and our pool is dark blue. From everything I read, I'm guessing it's yellow algae?

I got the TF test kit, and I have been testing a lot over the last week. I was actually under the impression that my husband "slammed" the pool last week, but he just shocked it. So now I'm wondering if I need to try to actually slam the pool to attempt to get rid of this dusty film we are seeing. I have about 12 gallons of 12.5% chlorine I picked up last week just waiting. The tests I've been doing over the last few days have shown about 3 FC and 0.5 CC. We have a salt chlorine system. Last night my last test was 4 FC and no CC, but we still have the dusty-looking, possible yellow algae. Even though there is no CC, we can still have yellow algae, right? Should just a SLAM be enough? Should I try something that's made for yellow algae? I had some water tested at a pool store before my test kit came, and they tried to convince me it's almost impossible that we have yellow algae.

Anyway, I have lots of questions, of course. And I also just want to make sure I'm not missing anything important. We have an autocover, and I'm assuming it's best to leave that open during the entire slamming process. I'm having a very annoying time getting the alkalinity down. Not sure why it was so high, but it was 190 when we opened the pool. I have it down to 110-120 range, and my ph is back up to about 7.5. Is there any reason to try to get alkalinity down more before slamming? Or is it enough to have a good ph? (I say between 110-120 because I can't make up my mind when it actually turns red lol). My CYA is about 45. I think that's a good number for CYA. If we slam, should we put all the pool tools in the pool for the whole process (I keep hearing to "shock" the tools too because of the possible yellow algae. We have a ton of trees and mess falling form them right now, and I'm at work all day. Is it enough to just clean all this stuff out every evening during this process, since I assume I need to leave the cover open?

also - a side question. is there any reason I need to increase CH? Pool is fiberglass and it's about 275-300. Pool store tested at 275. I got 300. They sold my husband a container of CH increaser, but I'm not sure we need it??

Any advice is much appreciated. TIA!..

Also I guess maybe I should include my latest test results summarized
FC - 3
CC - 0
ph - 7.5
alk - 110ish
CYA - 45
CH - 300

 

[stoles]

Of course, I posted this and the site suggested some similar posts. Found one that took me to a particular process for mustard algae... Still have a few more Qs though!

 

[mknauss]

Follow the SLAM Process. It might be yellow algae, but that is quite rare.
Your CYA is 50 ppm, round up.
No need for calcium. Return the product. Any CH above 100 ppm is fine.
You can close the cover during the SLAM, simply be sure to open it each day for a few hours with sun on the surface of the pool.
No need to bother with TA prior to SLAM. After just manage your pH and the TA will resolve itself.

I doubt the tools, etc are an issue.

Keep the organic debris cleaned out as much as possible.

Have you done an Overnight Chlorine Loss Test? I wonder if what your are seeing is pollen.

 

[stoles]

Follow the SLAM Process. It might be yellow algae, but that is quite rare.
Your CYA is 50 ppm, round up.
No need for calcium. Return the product. Any CH above 100 ppm is fine.
You can close the cover during the SLAM, simply be sure to open it each day for a few hours with sun on the surface of the pool.
No need to bother with TA prior to SLAM. After just manage your pH and the TA will resolve itself.

I doubt the tools, etc are an issue.

Keep the organic debris cleaned out as much as possible.

Have you done an Overnight Chlorine Loss Test? I wonder if what your are seeing is pollen.

Thanks! I did the last OCLT last week to try it out. Dropped 2 overnight. I dropped .5 overnight last night but the salt system was on and I had turned it down yesterday a bit because we're still trying to fine tune the output we need to keep FC at a good level.

 

[mknauss]

Be sure the SWCG is turned off for the OCLT.

 

[stoles]

After reading more about the mustard algae on the instructions here, I feel like that's probably what we have. It's definitely forming on the walls mostly in the areas that have the least sunlight during the day. It also did not show up when my husband shocked the pool last week for the next 4 days or so until the chlorine level actually got down below five.

 

[mknauss]

Ok. Then complete the normal SLAM process then do the mustard algae protocol. One day of high FC then an elevated FC for several weeks after that.

 

[stoles]

Ok. Then complete the normal SLAM process then do the mustard algae protocol. One day of high FC then an elevated FC for several weeks after that.

Thanks for the tips! Just wondering how elevated on the elevated free chlorine level for the next few weeks.
I reread the link below and didn't see anything about that part but I totally could have missed it.

Mustard Algae

Today We are going to show you how you can get rid of mustard algae in your pool. By following the steps in this guide and with no expensive chemicals.

www.troublefreepool.com

 

[mknauss]

Chlorine/CYA Chart

EDIT: You will find a simplified and standardized version of this chart at Pool School, Chlorine / CYA Chart. Chlorine/CYA Chart by Chemgeek FC = Free Chlorine in parts-per-million (ppm) CYA = Cyanuric Acid in parts-per-million (ppm) CYA ........... Min FC3 ..... Target FC ...... Yel/Mstrd...

www.troublefreepool.com

Keep it above the Yel/Mstrd minimum.

 

[stoles]

Well. I started the slam officially on sunday. I had a couple of days working from home this week so I knew I could keep up with everything a little better. My water is actually pretty clear and really hasn't been that cloudy for the last 2 months. I have been accumulating a Dusty grayish Brown build up on the bottom of the pool between brushings and vacuuming everyday. I assume that is dying algae? Hopefully. I'm also hoping that it is new Dead algae and not somehow getting back into the pool from the filter. I'm still failing the overnight test but my CC is usually 0.5 or less. I've actually only had one time where I needed more than one drop to clear up the pink the second time.

Anyway, I was reading through the forums and I realized I hadn't considered that there could be something consuming chlorine on the bottom of my auto cover. I don't really know of any way to look at the bottom of the auto cover though. LOL. I have been keeping the auto cover open as long as I'm home and it's not raining, which has been most of the slam so far. I closed it for a while when it was windy a couple of days ago and I closed it most of one day while it was raining. Should I give the cover more time being closed so the chlorine can work on possible growth on the bottom of it? I never really thought about that before. I've just been keeping it open because everyone keeps telling me that it's not good to expose the auto cover to high amounts of chlorine for extended periods of time.

I know I am Forgetting to ask a couple of things that I thought of earlier today but I'll keep this comment from getting any longer. Using voice text so please excuse any weird spellings and capitalization.

 

[stoles]

This is what my water looked like 2 days ago when I was trying to take a picture of what is apparently some kind of depression in the bottom of the pool.

 

[stoles]

@mknauss
Also this is kind of new today. I forgot this guy was in my basket and he is covered in the residue you see here. Also the whole inside of the circular white part of the skimmer had a disgusting layer of this dark greenish Gray gunk. I wiped it off with the skimmer sock in the picture but didn't think to get one of what it looked like. Could this be dead algae?

 

[mknauss]

Could this be dead algae?

Partly. Good ole gunk. Oils, old sunscreen, etc.

 

[stoles]

Partly. Good ole gunk. Oils, old sunscreen, etc.

I'm hoping for the dead algae. haha. We've barely had any people or sunscreen in the pool since it's had water in it. I've never seen so much of that before, even on the scum bug. FX something worthwhile is happening in there.

I did not pass the OCLT again last night, but I think I'm getting closer. Only had a drop of 1.5. I need to order some more R-0871 though. I went a little nuts repeating the tests a few times because I was getting significantly different results. Trying to perfect my routine, and used way too much before I realized it.

I do keep getting the same dusty, light yellow looking film every morning in the same place on the side in the shadiest part of the pool. It's not as thick as it once was. I brush it away and then don't see it until the next morning. Should I repeat my CYA test to make sure I'm using enough chlorine? This is the 5th full day of Slamming.

 

[stoles]

@mknauss I see you have a fiberglass pool. I have some off-this-topic questions about mine and some possible and definite pool builder mistakes. What is the best forum to ask that in. I'm kind of hoping there are some fiberglass pool experts in here.

 

[mknauss]

dusty, light yellow looking film

Once you complete the SLAM, do the one day Mustard Algae protocol. See Mustard Algae

If you have items pertaining to the fiberglass shell, post in Everything Else those questions. @Texas Splash has a fiberglass pool and is a great resource.

 

[stoles]

I'm just totally at a loss today. The yellow seems to be coming back faster in more places on the wall. We were overwhelmed with pollen yesterday, but I really don't think I'm seeing pollen on the walls of the pool inside the water.
First pic is the waterline this morning. Pool was open all night. Next are what the yellow stuff looks like.
I feel like this is going to be neverending.
I redid the CYA test and got close to 40.

 

[stoles]

Camera doesn't do justice to the color of the yellow dust stuff that I've suspected is mustard algae.