Algae? Pollen? Or am I taking crazy pills?

Scooch

Active member
Jul 16, 2013
29
I have been diligent about keeping my FC levels in the appropriate range all summer. CYA is 40, and I haven't let FC dip any lower than 5 since May. Typically it has been in the 7-10 range. In the past few days I've seen what looks like "algae" in small clusters at the bottom of my pool (4 feet deep, above ground, vinyl lining). When I brush it immediately turns to a fine yellowish-greenish dust. Water is crystal clear aside from that. And there is no evidence of the liner surface slickness that algae usually brings. Feels clean to the touch.

I guess it could be algae, but given how high my FC levels have been, I just don't understand how it could have taken hold.

Anyone encounter this issue? I'm baffled, and would prefer not to SLAM and take the pool out of commission for several days if I don't need to.
 

Scooch

Active member
Jul 16, 2013
29
You could do an OCLT to see. BTW, your pool is perfectly fine to use while doing a SLAM.
Thanks for the reply! I'll do a formal OCLT, although I test daily, and, informally, it doesn't seem like I'm losing any FC overnight.

As to the SLAM... is it really safe to have swimmers in the pool if the FC level is 16+? I've assumed that was dangerous, and needed to get the FC level below SLAM level before people could use the pool again.
 

Scooch

Active member
Jul 16, 2013
29
Nope. The CYA buffers the chlorine in the water. A FC/CYA of 9/60 is less harsh than a pool with no CYA and FC=1
Got it. But just so I totally understand, in your example (FC = 9, CYA = 60) that's not SLAM level. If I amp up my pool to, say, an FC of 18, while the CYA is 40, people can go in? The CYA/FC chart says SLAM level would be 16 with a CYA of 40.
 

Scooch

Active member
Jul 16, 2013
29
Yeah, I just picked one. With your CYA of 40, a FC of 16 will probably not even be noticable to swimmers.
Fantastic! I've been concerned since I started with TFP 5 years ago that I'd have people swimming in a toxic chlorine soup!
 

Wobblerlorri

Bronze Supporter
I've been SLAMming for the last week and getting in every day to sweep and vacuum. I'm still alive LOL. Seriously though, I don't notice any difference in the feel of the water or detected any chlorine smell. Y'all hop on in, as long as you can see the bottom of the deep end.
 
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frogabog

Gold Supporter
LifeTime Supporter
Jul 16, 2010
2,833
Portland, Oregon
My dad had MRSA in his spine for years. 14 surgeries later, it was that darn cadaver bone they'd put in his spine. My boys also used to get MRSA infections in their skin now and again when they were younger. My ex also got it a few times. My daughter and I did not. Chances are it was passed from my dad somehow. No one has gotten it in years though, thankfully.

I say the above only to point out that my dad's Dr. told him to tell us to soak in a tub once a week with 1 cup of bleach in it as a preventative measure. IDK what a bathtub holds, but it's probably 100 gallons or less. 1 cup of bleach in 100 gallons is very high FC. It appears no one died soaking in high FC with this method, else why would the Dr. say to do it?
 
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Scooch

Active member
Jul 16, 2013
29
I performed the OCLT and it appears the pool lost, at most, 1.0 of FC. So right on the borderline. And still some of the greenish-yellowish “dust” on the bottom. Water is totally clear though. So perplexing!
 

B_A_T

Active member
Jun 25, 2019
32
Chicago
I have been battling the same issue (questioning algae or pollen) for I had similar symptoms. I am in the middle of a SLAM right now and seeing positive results. Before you say the answer is obvious (the proverbial; wait, there's more), I realized that my light brown deposits were typically in the exact same areas like stair corners, tanning deck corners and same locations on the floor. To take it a step further I realize that it was also close to returns and in fact re-aimed the one return where the largest deposit kept showing up.

I was already in SLAM (since Sunday) when I had this revelation and I also had installed a skimmer sock (also on Sunday). Since I have been seeing a significant reduction in "brown stuff" and will continue the SLAM until it is gone 100%. My point is, considering the locations were consistent wouldn't that lend itself to bring pollen? Changed out the sock last night (it was nasty), and deposits were almost gone today but will continue.

Short story long, are your deposits reappearing in similar locations after you brush or are they random all over and on walls?
 

Scooch

Active member
Jul 16, 2013
29
I have been battling the same issue (questioning algae or pollen) for I had similar symptoms. I am in the middle of a SLAM right now and seeing positive results. Before you say the answer is obvious (the proverbial; wait, there's more), I realized that my light brown deposits were typically in the exact same areas like stair corners, tanning deck corners and same locations on the floor. To take it a step further I realize that it was also close to returns and in fact re-aimed the one return where the largest deposit kept showing up.

I was already in SLAM (since Sunday) when I had this revelation and I also had installed a skimmer sock (also on Sunday). Since I have been seeing a significant reduction in "brown stuff" and will continue the SLAM until it is gone 100%. My point is, considering the locations were consistent wouldn't that lend itself to bring pollen? Changed out the sock last night (it was nasty), and deposits were almost gone today but will continue.

Short story long, are your deposits reappearing in similar locations after you brush or are they random all over and on walls?
We’re experiencing very similar things. Yes, the floor deposits occur in generally the same areas every day. And nothing at all on the walls, entirely the floor. Plus, no slickness in those floor spots whatsoever.
 

B_A_T

Active member
Jun 25, 2019
32
Chicago
We’re experiencing very similar things. Yes, the floor deposits occur in generally the same areas every day. And nothing at all on the walls, entirely the floor. Plus, no slickness in those floor spots whatsoever.
Sounds like we may be fighting the same fight, I will be interested to hear the "expert" opinions here.
 

pollyAnna

Member
Jul 15, 2019
23
Princeton NJ
I have been battling the same issue (questioning algae or pollen) for I had similar symptoms. I am in the middle of a SLAM right now and seeing positive results. Before you say the answer is obvious (the proverbial; wait, there's more), I realized that my light brown deposits were typically in the exact same areas like stair corners, tanning deck corners and same locations on the floor. To take it a step further I realize that it was also close to returns and in fact re-aimed the one return where the largest deposit kept showing up.

I was already in SLAM (since Sunday) when I had this revelation and I also had installed a skimmer sock (also on Sunday). Since I have been seeing a significant reduction in "brown stuff" and will continue the SLAM until it is gone 100%. My point is, considering the locations were consistent wouldn't that lend itself to bring pollen? Changed out the sock last night (it was nasty), and deposits were almost gone today but will continue.

Short story long, are your deposits reappearing in similar locations after you brush or are they random all over and on walls?
What is a skimmer sock? I too am seeing sediment - sand like, dust like - on the steps and in the seat area. But no other obvious signs of algae. I just passed the Over night free cl test and have zero cc.
Thanks!
 

frogabog

Gold Supporter
LifeTime Supporter
Jul 16, 2010
2,833
Portland, Oregon
Try brushing often to keep those particles in suspension so the filter can catch them. Sounds like they're depositing in the low flow areas. Maintaining SLAM FC as long as you see this will help make sure they don't come back to life.
 
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