Is this sand, dirt, or dead brown algae?

[AboveGroundInflatable]

I frequently find this stuff accumulating in the creases at the bottom of my pool (12' x 30" round, ~1700 gallons). At first, I thought it was simply dirt particles from recently added water that were too small to be captured by my SWG but now I'm not so sure. Within 30 minutes of vacuuming my pool, this stuff begins to accumulate once more, even weeks after adding water to the pool. My pool is relatively balanced, water is always clear, and chlorine levels are stable as is the salt. Alkalinity and PH is on the higher side, although we have very hard water where I am so that's a constant battle. I've yet to see algae accumulation on the sides of the pool which adds to my confusion. If this is algae, where is it coming from?

 

[YippeeSkippy]

Can you pick it up? Is it gritty? Can you smear it on a piece of paper?
What are your test levels for:
FC
CC
pH
TA
CH
CYA
Salt
You said "balanced" but I don't know what you mean by that without actual figures?

How often do you test your water, and which test kit are you using?

too small to be captured by my SWG but now I'm not so sure.

Your SWG produces chlorine, it doesn't capture dirt.

Maddie

 

[Gary Davis]

There are a lot of good ideas over here for using a turkey baster or coffee filter to collect the dust to assay it.

Fine dust collection, drying, and subsequent direct chemical assay on that fine dust, as dust​

 

[AboveGroundInflatable]

There are a lot of good ideas over here for using a turkey baster or coffee filter to collect the dust to assay it.

Fine dust collection, drying, and subsequent direct chemical assay on that fine dust, as dust​

This is an excellent recommendation, thank you.

 

[AboveGroundInflatable]

Can you pick it up? Is it gritty? Can you smear it on a piece of paper?
What are your test levels for:
FC
CC
pH
TA
CH
CYA
Salt
You said "balanced" but I don't know what you mean by that without actual figures?

How often do you test your water, and which test kit are you using?


Your SWG produces chlorine, it doesn't capture dirt.

Maddie

Can you pick it up? Is it gritty? Can you smear it on a piece of paper?

• No. The stuff dissipates fairly quickly once the surrounding water is disturbed.

What are your test levels for:

• FC - 3ppm
• CC - 1ppm
• pH - 7.4
• TA - 60
• CH - 250
• CYA - 30
• Salt - ~3000 at last measurement.

How often do you test your water, and which test kit are you using?

• Typically once a week unless I am out of town on the weekend, more frequently if the any of the above statistics get out of control. I use a combination of various test strips to identify if/when things are way out of whack along with my TF Kits set for accurate measurements. The values above came from the TF Kits.

Your SWG produces chlorine, it doesn't capture dirt.

• You are correct. The sand filter attached to my SWG is responsible for waterborne particles. I'll try to be clear going forward.

EDIT: Updated PH and TA levels to reflect addition of muriatic acid. Still working on CYA levels.

 

[YippeeSkippy]

Well I suspect your FC level has dropped lower than 3 at times and it looks like you have algae. I say that based on low FC, CC of 1, dust of questionable type..... so now its time to get serious and kick some algae butt with a SLAM Process.

Please review the above link and ask any questions that arise.

Maddie