Well, Here We Go Again with the Algae

[Seadweller]

I just don't get it. I've been keeping up with the pool to prevent this from occurring, but every year the algae rears its ugly head despite a nearly perfect chemical balance:

FC = 7
CC = 0
PH = 7.6
CY = 70
AK = 80

Is it possible that a dead spot in the circulation is causing this? The algae appears on the same wall every time. The way the wall curves, along with the positioning of the jets, I have no direct way of increasing circulation in that area. Perhaps a modified jet of some sort?

 

[Pool_Medic]

Is it happening in the same spot?

 

[Jimrahbe]

S,

With a CYA of 70 (not recommended) your FC should be kept between 8 and 10.

If you get algae, you are not keeping your FC high enough for your CYA. While algae might start in a place with less circulation, the problem is not a circulation issue, it is an FC issue.

I suggest that you do a SLAM.. SLAM Process

I'd first drain a little to get your CYA down to 40 or so.

Thanks,

Jim R.

 

[Seadweller]

Thanks guys....Yes, it's in/on the same place/wall every time. Good to know about the CYA/FC relationship. I haven't tested CYA in 4-5 days, but I'll do so again today as we did have some rain, and will adjust FC accordingly. I assume that keeping FC in the 8-10 range is OK?

 

[cowboycasey]

You are in Florida and there are many having the same problem.. you get lots of rain and your FC and CYA can get diluted fast and the next thing you know your CYA is 50 and FC is at 5.. The Algae gets a foothold in that same spot and then its on... This is what I have been telling other from Florida to see if it will stop the outbreaks or help any..

test CYA Weekly and try to keep at 80
Take FC to 8 and see if it helps
Try to run the pump all day or longer and have the SWG running for the same amount of time... For me I run less hours and run my SWG higher but I think it will work better for you to get chlorine coming into the pool for a longer time..

 

[Jimrahbe]

Sead,

Sorry, but I did not see that you have a saltwater pool, so a CYA of 70 is just fine and an FC of 7 is also ok.

That said, the same basic idea still applies. The only way to get algae is if you let your FC get too low. For saltwater pool, a CYA of 70 means your FC should be at 5 ppm.

You should not try to keep your FC between the minimum of 3, and your target of 5 ppm. You should keep your FC at your target of 5 or above. You never want the FC to get close the minimum of 3 ppm. Think of the minimum as a cliff you never want to fall off.

Thanks,

Jim R.

 

[YippeeSkippy]

Are you good about brushing your pool? Or do you have a robot that has taken over that task?? Brushing helps you avoid algae hidden under biofilm which makes it resistant to chlorine.

 

[Seadweller]

Thanks for the input gang. I've never seen the FC get below 7, so that's why I'm puzzled. I bought a different kind of return off of Amazon, and it's actually a 90 degree elbow. Installed it this morning and the circulation in the pool has improved dramatically. I guess we'll see if lack of circulation in that "pocket" of the free-form pool was part of the issue.

 

[pb4uswim]

Thanks for the input gang. I've never seen the FC get below 7, so that's why I'm puzzled. I bought a different kind of return off of Amazon, and it's actually a 90 degree elbow. Installed it this morning and the circulation in the pool has improved dramatically. I guess we'll see if lack of circulation in that "pocket" of the free-form pool was part of the issue.

Can you post a link to that elbow?

I’ve had the same problem as you and I’m out of ideas. Though, I have thought it’s a circulation issue. Wishing you luck figuring this out. I’ve just kinda learned to live with it. Brush a lot and keep chlorine at the high end of recommended based on CYA. It helps but I’ve not found it to cure the persistent algea.

 

[Mdragger88]

Is this a shaded area? If so, It’s possible it’s mustard algae - the remedy is SLAM Process then after passing all 3 end of slam criteria moving on to the MA protocol followed by maintaining higher maintenance fc levels (15% of cya level) for an extended time.

Mustard Algae

Today We are going to show you how you can get rid of mustard algae in your pool. By following the steps in this guide and with no expensive chemicals.

www.troublefreepool.com

Chlorine/CYA Chart

EDIT: You will find a simplified and standardized version of this chart at Pool School, Chlorine / CYA Chart. Chlorine/CYA Chart by Chemgeek FC = Free Chlorine in parts-per-million (ppm) CYA = Cyanuric Acid in parts-per-million (ppm) CYA ........... Min FC3 ..... Target FC ...... Yel/Mstrd...

www.troublefreepool.com

Got any pics?

 

[Seadweller]

Well, figured I'd report back so folks can hopefully gain from some practical experience. Since installing the elbow fitting several days ago, the algae has not appeared on the wall. I also raised the chlorine level, but still believe there was a dead spot in that section. The pool originally had 2 returns and a fitting for a pressure cleaner. When I had the pool remodeled, I had them add a suction fitting for a pool cleaner, and converted the pressure fitting to a return jet. Problem is, it's in a poor spot. Adding the elbow significantly improved water circulation and completely eliminated the dead spot.

Can you post a link to that elbow?

I’ve had the same problem as you and I’m out of ideas. Though, I have thought it’s a circulation issue. Wishing you luck figuring this out. I’ve just kinda learned to live with it. Brush a lot and keep chlorine at the high end of recommended based on CYA. It helps but I’ve not found it to cure the persistent algea.

https://www.amazon.com/gp/product/B09Q8PHGSP/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&th=1

Is this a shaded area? If so, It’s possible it’s mustard algae - the remedy is SLAM Process then after passing all 3 end of slam criteria moving on to the MA protocol followed by maintaining higher maintenance fc levels (15% of cya level) for an extended time.

Mustard Algae

Today We are going to show you how you can get rid of mustard algae in your pool. By following the steps in this guide and with no expensive chemicals.

www.troublefreepool.com

Chlorine/CYA Chart

EDIT: You will find a simplified and standardized version of this chart at Pool School, Chlorine / CYA Chart. Chlorine/CYA Chart by Chemgeek FC = Free Chlorine in parts-per-million (ppm) CYA = Cyanuric Acid in parts-per-million (ppm) CYA ........... Min FC3 ..... Target FC ...... Yel/Mstrd...

www.troublefreepool.com

Got any pics?

The area is in the sun from 11AM until sunset, and later in the afternoon it's getting beamed directly by the sun. It's definitely green algae. CC's are at 0, so I think the growth was isolated to that one section due to the lack of circulation which likely caused the water in that "pocket" to warm above the average temperature of the pool. Just conjecture on my part, but the algae hasn't returned to that wall since I installed the new fitting.

 

[Seadweller]

Here's a picture with the new fitting installed. You can see, based on the location of the jet, that there was really no way to direct return flow into the "pocket" where the skimmer is located with a standard eyeball. This fitting allowed the flow to be directed right into the area. Now, you can actually see the pool water circulating, and a mini whirlpool will occasionally develop in the deep end.