Algae or dirt?

[TigerFanatic1]

I’ve vacuumed to waste about 3 times (really slow), but still have about the same amount of sediment. Pool turned to swamp over winter and I’ve had this for about 2-1/2 months since SLAM.

FC - 9
Cc - 0
CYA - 30
PH - 8
TA - 110
CH - 100

 

[Texas Splash]

Sure looks like algae. Does it brush-away into a cloud or is it stuck on the liner and doesn't budge?

 

[Richard320]

An Overnight Chlorine Loss Test will tell you for sure.

And why vacuum to waste? All that water exchange will mess with your chemistry. Let the filter strain it out.

 

[TigerFanatic1]

It brushes to a cloud, but the overnight test was 1 ppm loss. I was going to waste because of the amounts of rain we had the past couple of months. If it’s a small amount I like to go to waste because I only have a sand filter.