Continuous Algae

[MauiArnel]

I have been experiencing algae outbreaks once a month which is addressed through a cartridge filter clean, SLAM, and daily brushing. However the algae will return within a few weeks following the SLAM. Also any time I adjust chemicals to lower pH, the algae will come back even quicker. I am hoping to get some direction on best way to clear up the water and maintain an algae free pool. Here are my current numbers (SLAMing):
FC - 10
CC - 0
CH - 325
TA - 160
CYA - 30
Salt 4500

 

[Newdude]

Hey Maui and belated Welcome !!!!!

If algae grows, your FC target was too low. There's no two ways about it.

How do you test and how often do you test ?
What time of day do you test ?

When does the SWG run and at what %?
 
What is your target ?

 

[MauiArnel]

I test daily every morning. My SWG runs for 12 hours a day at 100% between 0600 and 1800.

As far as my target, I try to keep my Cl at 6 and pH at 7.8

 

[Newdude]

Ok so producing during daylight helps a bunch. There will be less daily swing doing so.

Your unit produces just under 4 ppm in 12 hours in 12k gallons and that's probably about what you're losing daily in SoCal this time of year.

Add liquid chlorone to get to 8ppm FC and let the SWG maintain that. Road test to see if the algae outbreaks stop.

 

[MauiArnel]

Passed the OCLT this morning.

FC - 12
TA - 200
CYA - 30

From reading, I believe I should have my CYA of at least 50 and my TA way lower, should I address the CYA first or lower pH to help with TA first?

 

[mknauss]

Add the CYA to get to 40 or 50 ppm.
Keep the pH in the 7's by testing every few days. As you do that, the TA will come down. Unless you are having issues with scale in your SWCG. If so, then you should more aggressively lower TA.

 

[JJ_Tex]

Sometimes when algae comes back shortly after ending a SLAM, that can be caused by algae hiding somewhere less obvious. Have you checked any stairs, ladders, behind lights, auto fill, skimmer weir doors, under the drain covers, auto fill, water features, or any other hiding spot?