How can this be?

[Dan P]

Hello all. I haven't had any issues during winter months with algae. Now as the pool temp has gone up, 81 degrees, I noticed a couple of yellow spots today. I have kept the FC at 10 to make sure algae didn't pop up. I went on a trip and brought it up to SLAM levels and today FC is at 18. I was brushing once a week but started to do it twice and run pump on low for 14 hours and high for 2. My question is how can algae grow with FC at 18? do I need to run the pump more for better circulation and/or brush 3 times a week.

CYA-70
TA-80
CL-375

 

[Patrick_B]

If it's Algae, it's unlikely it's caused by anything more than the FC slipping too low at some point(s). It happens, and other causes are rare. How long were you gone, and how low could the Chlorine have gotten while you were away?

Brushing a few times a week usually sufficient in a majority of pools, but you cant do it too often. I suggest a full and complete slam to the letter before you decide to change your run times. Of course, excellent FC/Cya management following for a while first as well. Then decide.

 

[cowboycasey]

it sounds like some spots are not getting flow and therefore the chlorine falls in those spots.. you may need to brush once a day or change how your returns are moving the water..

 

[duraleigh]

I noticed a couple of yellow spots today.

that doesn't sound like algae. got some pics?

 

[Dan P]

I was only gone for 4 days. Sorry, no pics since I brushed it off. The yellow spots were on the wall at the deep end almost at the floor and at the corner of the deep end swim out. There has been a lot of debris lately in the pool from neighbors tree but I have skimming the leaves out and the filter was cleaned yesterday. Maybe I will turn one of the return lines to point lower.

 

[YippeeSkippy]

Here in Georgia we've got yellow pollen every place. Could this be pollen in your pool?

 

[Dan P]

There's some pollen falling from the tree but it's more brown than yellow.

 

[Texas Splash]

I like Casey's suggestion about checking the flow of water in your pool for now. Circulation can certainly be a factor. One local trick is to toss a few ping pong balls in the water and see how they flow. If you find little/no movement near that same area where you saw the brownish/yellow stuff, adjusting a jet in that direction may help - or simply increase manual brushing for that one area (if it's just isolated to that area). Also, next time you see anything like that growing against the wall, let us know or post a pic. Perhaps it's not your standard, everyday type of algae. We'll see.

 

[Matrioux]

We have green pollen in NC that turns yellow when wet, if circulation isn't the issue, I would think pollen.

 

[Dan P]

Question, if it's pollen why is it only on the sides and not on the floor? I'm thinking it's more of a circulation issue.