Frustrated with algae control!

[Rost-Lufer]

Hey y'all,

I posted a few weeks/month ago and thought I finally had a true TFP! Nope! Algae is back....grrrrrrrrrrrrrrr.

Not sure what's going on. I keep my FC level at the high end of the recommendation using the pool math app. For first time since pool install middle of last summer I had 2-3 weeks of a beautiful, crystal clear pool. Before this I had algae showing up every 2-3 days. After failed SLAMS due to operator error(always the operator right?)I finally followed SLAM rules to a 'T' and pool looked best it has ever....for a few weeks. Levels have never dropped below pool math recommendations. Without looking, I think lowest FC level was 3.5, CYA at 40. Usually level is at 4-5 when I test. When I add chlorine I take levels to 7 or 8ppm which is at/above recommended FC level based on 40 CYA.

What am I missing? As long as FC is at recommended level I thought algae would not form?

 

[reggiehammond]

CYA 40, minimum is 3. 3.5 FC is awfully close to minimum and maybe you had knocked algae back during previous SLAM, but not fully eliminated. You should also check ladders/stairs, weir doors and anything else that might be harboring some hidden algae.

Are you testing daily? Your poolmath logs have some pretty big gaps.

 

[Newdude]

You are only testing 10ml of thousands of gallons and it's a momentary snapshot of that exact spot. A ray of sunshine on the other side of the pool may make it test lower over there before it's mixed up.

Then all pools have poor circulation areas or dead spots to make it even more sketchy at times.

If you're getting algae, your target is too low for that point in the season.

 

[Rost-Lufer]

CYA 40, minimum is 3. 3.5 FC is awfully close to minimum and maybe you had knocked algae back during previous SLAM, but not fully eliminated. You should also check ladders/stairs, weir doors and anything else that might be harboring some hidden algae.

Are you testing daily? Your poolmath logs have some pretty big gaps.

Last slam I pulled all wier doors, ladder, bottom drain covers and cleaned thoroughly. I was gone for a few days and had wife adding a certain amount of bleach everyday. When I got back FC was at 5 so it think it worked well.

 

[proavia]

Last slam I pulled all wier doors, ladder, bottom drain covers and cleaned thoroughly. I was gone for a few days and had wife adding a certain amount of bleach everyday. When I got back FC was at 5 so it think it worked well.

If algae is coming back, seems it didn't work well enough.

Anytime I leave for more than a couple of days, I bump the FC to a few points higher than top of target. Even going to 1/2 SLAM level FC will work to provide an extra buffer.
While going to half of SLAM level may use a little more chlorine while I'm gone, I haven't had to worry about seeing algae on my return.

 

[Rost-Lufer]

If algae is coming back, seems it didn't work well enough.

Anytime I leave for more than a couple of days, I bump the FC to a few points higher than top of target. Even going to 1/2 SLAM level FC will work to provide an extra buffer.
While going to half of SLAM level may use a little more chlorine while I'm gone, I haven't had to worry about seeing algae on my return.

I should have clarified the algae showed up before I left for a few days. As I am the one who takes care of the pool I just had my wife add bleach everyday.

 

[proavia]

I should have clarified the algae showed up before I left for a few days. As I am the one who takes care of the pool I just had my wife add bleach everyday.

Ok - then up your target FC so to stay well above minimum - better yet, well above the lower end of the target range.

If you presently have algae or fail an Overnight Chlorine Loss Test, it's time to do the SLAM Process.