Algae in 8ppm FC?

Texas Splash

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Jun 22, 2014
33,444
Texas, San Antonio/Marion, South-Central Area
Pool Size
17888
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Chlorine
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SWG Type
CircuPool RJ-45 Plus
Question - what is in the bottom of my pool? Is that dead algae that just accumulates in various places where there’s poor circulation? Or, is that live algae, which of course with my chlorine so high seems unbelievable.
If it's green it still has some life to it. Dead algae will become more white or grey in color. Some things that slow down the algae killing process is not maintaining the FC SLAM level consistently, a CYA higher than expected resulting in an FC that's too low, and/or not brushing and disturbing the algae enough.

I don't see a pic on this thread, so this is all assuming it actually is algae and not something else. I know that'[s been discussed quite a few times, but you have passed an OCLT previously, so now I can't help but wonder what that mystery stuff is in there. Your water cold yet or are you still heating it?
 
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pb4uswim

Well-known member
Jul 23, 2020
328
Michigan
My water is still pretty warm yet. I’m heating it, but it’s over my setting. It’s hot here until next week. Water temp is 87 right now.

I’ll try to get a picture of it tomorrow before I start my SLAM. It is a dull green and it disappears when I brush it. It’s in two places. It’s not on my ledge where there was an issue earlier in the year. This stuff also looks different than that stuff did. I’m leaning toward the other stuff being pollen, but this seems different. SLAM’ing it for a couple days won’t hurt anything and will make sure things are clear as I get close to closing in about a month.
 
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Newdude

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Jun 16, 2019
10,892
NY
Late summer i always got another round of pollen like dust. Not exactly sure if it was the farmers planting the fall crops kicking up dust or one last round of crud from the oaks but I had lots of poofy stuffs right about now that wasn’t algae.
 
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pb4uswim

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Jul 23, 2020
328
Michigan
Late summer i always got another round of pollen like dust. Not exactly sure if it was the farmers planting the fall crops kicking up dust or one last round of crud from the oaks but I had lots of poofy stuffs right about now that wasn’t algae.
Interesting. I’ll SLAM it for a day, let it drift down the next and see if I pass OCLT. Last time I lost 1ppm overnight. I’d feel better if I passed with .5 or zero loss.
 
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Newdude

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Interesting.
I haven’t built the pool yet but now I back up to farmfield. Most of the corn behind me got cut recently and my windows and patio are full of dust/dirt. The pool would have been too.

I’m not saying that yours is/isn’t, only that this is a suspicious time of year at our general latitude. It would certainly explain the how, considering your elevated FC.
 

pb4uswim

Well-known member
Jul 23, 2020
328
Michigan
I haven’t built the pool yet but now I back up to farmfield. Most of the corn behind me got cut recently and my windows and patio are full of dust/dirt. The pool would have been too.

I’m not saying that yours is/isn’t, only that this is a suspicious time of year at our general latitude. It would certainly explain the how, considering your elevated FC.
I put the SWG on 100% last night and this morning there doesn’t appear to be any algae. Maybe it’s because the sun hasn’t hit the pool yet? So, no picture to be had. Anyway, the chlorine is at 15 and I’m going to start my SLAM. I shut off the SWG and will turn the pump up to 75% and give it the first liquid chlorine in a few minutes. Thanks for your input.
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Jun 22, 2014
33,444
Texas, San Antonio/Marion, South-Central Area
Pool Size
17888
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
CircuPool RJ-45 Plus
full
 
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pb4uswim

Well-known member
Jul 23, 2020
328
Michigan
I’m not sure if these add anything but I tried to take some pictures this morning. Is so hard to get a picture of something underwater.

2157656B-E593-4DEF-A609-700ED35FDE72.jpeg
A75267CB-3C3C-4BB4-A06D-60469651B15E.jpeg

The first picture is a close up. The second pictures shows the blob from eye level. It’s about the size of a dollar bill. I’ll post my observations in the next post.
 
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pb4uswim

Well-known member
Jul 23, 2020
328
Michigan
SLAM update:

I was disappointed to see the above blob after I SLAM’ed yesterday. Yesterday, I kept the chlorine level above 20 all day. It seemed hard to get to my target of 25 but it was a very hot sunny day. Toward evening, I got frustrated and dumped in a gal of chlorine. That was around 5pm. At my 7pm test chlorine was up to 35. Then the storm came and we got a couple inches and some debris in the pool over night. I checked the chlorine this morning and it was down to 24. I’ve put the SWG on to 100% and will run that today and keep chlorine over 20.

My goal is to have chlorine around 20 tonight at sunset and do my OCLT. I’m thinking whatever the blob is, it’s not live algae given the chlorine level overnight and yesterday. Note that nothing appeared throughout the day yesterday as I was SLAM‘ing.
 

Newdude

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Jun 16, 2019
10,892
NY
It’s persistence certainly points to either black algae which is a bacteria and not really and algae, or Mustard Algae. It’s not yellowish to easily be identified as Mustard, and Black algae typically doesn’t take root in vinyl pools, but those are the 2 usual suspects when persistent after a successful SLAM. You certainly didn’t slack on the SLAM as we were there too and can attest to your vigilance. (Great job again !! But here we are so there’s something left to be done).

Read up on the Black algae and do the paper test. Maybe it’s still hiding in a non Vinyl part like the light niche and being reintroduced. Then click the link at the bottom for Mustard and see if any of that is relevant.

 

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pb4uswim

Well-known member
Jul 23, 2020
328
Michigan
Clarification, my pool is fiberglass. As for the lights, they are small LED’s. I‘ve never removed them but I would think they are sealed. I can take a picture if necessary.
 

Newdude

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Jun 16, 2019
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NY
Clarification, my pool is fiberglass
My bad, but same impervious characteristics as the vinyl. Unlikely for black algae but not impossible if it’s somewhere else. Others would know about your specific lights. Refresh my memory if there is anywhere else that could be suspect ? Water features, auto fill, ladders etc ?
 

pb4uswim

Well-known member
Jul 23, 2020
328
Michigan
My bad, but same impervious characteristics as the vinyl. Unlikely for black algae but not impossible if it’s somewhere else. Others would know about your specific lights. Refresh my memory if there is anywhere else that could be suspect ? Water features, auto fill, ladders etc ?
I have laminars (water features), but I haven’t used them much this year and not recently. No ladder, no auto fill except that storm last night :) ), just the weir door and the lights and I don’t know how the lights are set in there.

Here‘s my one thought. About a week ago, DD had some kids over (friends of our grandkids). I just confirmed with her that they used some blow up toys that had been sitting around the pool for most of the season, not being used. Accordingly, they have some mold on them (mold - another name for algae?). Of course my DD said they sprayed them off, but they would need a bleach product cleaning. I should have just thrown those Crud toys away. So, that may be where this came from, but the layperson in me thinks the amount is too small to have caused this especially given that I’ve stayed up on my chlorine. And yesterday should have cleared out anything they brought into the pool.

On the laminars, thanks for bringing that up. I’ll run them to make sure I get some of the current high chlorine water in that part of the system.
 

Newdude

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TFP Guide
Jun 16, 2019
10,892
NY
So, that may be where this came from, but the layperson in me thinks the amount is too small to have caused this especially given that I’ve stayed up on my chlorine.
+1. You’ve had plenty of FC to eat up any small doses of ickies.
On the laminars, thanks for bringing that up. I’ll run them to make sure I get some of the current high chlorine water in that part of the system
The hunt is ON !! It’s clearly coming from somewhere and almost certainly not the water.
 
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pb4uswim

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Jul 23, 2020
328
Michigan
I’ll check the back of the weir door. It’s obviously hard to view. Is there a way to remove it so I can better inspect the back of it? Otherwise I’ll try a mirror.
The pool, being fiberglass only has three things that break the seal of the shell. The outlet jets, the lights and the skimmer. The steps are integrated as part of the fiberglass shell, so there’s no ladder. I’ll post a couple more pictures. Give me a couple minutes.
 

pb4uswim

Well-known member
Jul 23, 2020
328
Michigan
847B52F9-AA01-4554-9FCC-963500ADD554.jpeg2AB0BF68-51C9-4F66-BA68-D73E4A363B29.jpeg
The first picture shows a light and an outlet. The second shows the skimmer and there’s a light below that.

I don’t know how to remove it, but the skimmer has what appears to be a frame around it. Maybe behind that? The lights? I know nothing about them to speculate whether they could be holding something.

Could it be it the filter canister? I haven’t opened that up for awhile. Haven’t felt a need - no pressure increase and have been using the hair nets for skimmer socks.
 

Newdude

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Jun 16, 2019
10,892
NY
I’ll check the back of the weir door. It’s obviously hard to view. Is there a way to remove it so I can better inspect the back of it?
Most are pressure fit and get bent a certain way to pop out the molded pins that hold them in place. Every inch being suspect of course all up in there, but particularly the foam that makes the door float at the top of it. Some folks found theirs all blacked up at the beginning of the season.
The first picture shows a light and an outlet. The second shows the skimmer and there’s a light below that.

I don’t know how to remove it, but the skimmer has what appears to be a frame around it. Maybe behind that? The lights? I know nothing about them to speculate whether they could be holding something
@Texas Splash might have ideas
 

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