Dirt/Dead Algae?

BuckeyeMac · May 13, 2020

Good morning fellow TFPers!

I had this same problem last year...I have these spots that show up on the bottom of the pool. You can see them in the attached pictures. It's really bad in the middle of the pool because last night we had some high winds & most of that is leaves/pine needles.However, I run the pool vac or sweep, etc, and these spots show up a few days later gain. We do live out in the country across from farm fields. I also use skimmer socks and we have REALLY HIGH Pollen...

I use liquid chlorine - 1/2 gallon per day is perfect for my pool. Should I be going up to "shock levels" once a week? Will that help? I'm not sure if those spots are dead algae, dust, pollen, etc...As you can see the water is crystal clear otherwise. I haven't adjusted pool chems yet because my water is still 55 degrees. However, last year when testing water once I got out of SLAM - I did not have any CC's in the pool all year.

Any help is great!

thetekgeek · May 13, 2020

It's hard to say from the pictures. You could do an OCLT. That should tell you if there is anything in the water that shouldn't be. Maybe also post a full set of test results.

woodyp · May 13, 2020

Dead algae is white. I assume you're talking about the dark spots? Only if dead algae is collecting some dirt. Can you get some between your fingers?

BuckeyeMac · May 13, 2020

So when I would swim last year, I took a pair of goggles and went to the bottom - it almost looks like brown dust. It sweeps up very easy. Once it gets disturbed, it disappears in the water. Test results are all in normal spec...

FC - 5
CC - 0
PH - 7.5
CH - 300
TA - 120
CYA - 20

Not worried about CYA low right now - its not warm out enough yet. Will raise once temps rise.

thetekgeek · May 13, 2020

I'd suggest an OCLT. Your description sounds to me like live algae.

BuckeyeMac · May 17, 2020

Okay so I did an OCLT last night.

FC last night was 5.5
This morning with a little bit of sun (about 2 hours) was at 5.0

Still getting a 0 CC reading

mknauss · May 17, 2020

Probably dirt. Keep an eye on it. Easy for you to go to SLAM level FC if you wish for a day or two.

Get your CYA up to 30 or 40 soon.

BuckeyeMac · May 17, 2020

mknauss said:
Probably dirt. Keep an eye on it. Easy for you to go to SLAM level FC if you wish for a day or two.

Get your CYA up to 30 or 40 soon.

Thanks! Yup - I’ve got CYA and a sock - will be putting it in probably today or tomorrow.

I’m pretty sure it’s dirt/pollen. My skimmer socks get a thick layer of yellow stuff by the end of the day.

I also just rinsed a couple of socks I used the last few days in a bucket...and at the bottom of the bucket is what looks like the bottom of the pool. I think we solved it.

Thanks for everyone’s help & input!