Help with Algae after slam

[knoball615]

Hello , I need guidance on what to do next. I just finished a SLAM on 5/19 . During the slam FC at 26-28 per pool math. The pool is clear but everyday there are sandy brown patches in the same spots of the pool every day. pic1 is 7pm last night after brushing- brushes to cloud
pic2 is 9am today the sandy stuff is along the left edge of pic .

pH 8
FC 11
CC 11
CYA 60
Salt 3000
CH 140

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I apologize for the huge pictures , I'm still fairly new to posting . I mostly just read all the helpful post

 

[southpond]

I think that might just be the dead algae that your filter isn't catching. I get predictable patches where it starts to drift down from the jets. I vacuum it up and eventually it all gets trapped in the filter. This spring I've had a lot of pollen as well which can do the same thing.

 

[cpmoshjr]

I am having the EXACT same issue and have been having it for over a year now. I'll do a SLAM, things will clear up beautifully and I'll be algae free for a while, and the BAM! I'm getting those same spots in the same part of my pool. If I vacuum it clouds up the water, and if I let it go for a while it starts to take over the pool again. I have been absolutely religious about balancing my water - my wife thinks I'm crazy - and I think I might be GOING crazy!

 

[duraleigh]

Yeah, that's likely dead algae. I would keep the FC around 8-10 ppm for a couple more days and watch it.

PS - don't forget recheck your pH when you drop below 11 ppm (today)

 

[duraleigh]

Since cpm posted too (don't hijack) so I will tell you both what's happening.

You are not holding your FC high enough, long enough.

You are allowing algae to grow right back by, at some point, allowing your FC to slip too low. Algae forms. Then it dies again when your chlorine elevates and it sinks to the bottom and collects in low spots, wrinkles, low circulation.

If you try to capture it, it will simply "poof" away. So, you need to vacuum or run your robot to get rid of it but the CAUSE is always low chlorine.

Algae simply cannot grow if the chlorine is adequate.

 

[cpmoshjr]

Sorry for the hijack and thanks for the info!

 

[knoball615]

Thanks for your comments, my husband also thinks I'm crazy . He loved the house we found but didn't want to buy it because of the pool LOL so I'm sneaking around trying not to let him know we have problems

 

[knoball615]

Thank you , I will keep it around 8-10 for a while and retest pH tonight . Should I just vacuum to waste or does that matter?

 

[knoball615]

What is a good way to determine if my sand filter is working properly?

 

[tim5055]

What is a good way to determine if my sand filter is working properly?

Well, as the status of the filer is kink of unknown to you, here is a nice weekend project: Deep Cleaning a Sand Filter

 

[duraleigh]

No need to vacuum to wast for that little amount. Suck it up with manual vacuuming or use your robot.

Tim has a great idea to inspect the sand filter.....I agree.