I have had a recurring black algae problem for a number of years which I have never been able to successfully defeat. Recently I began following this site and bought my TF-100 which has been very helpful. In reading the SLAM and Black Algae posts, I felt ready to tackle the project. I adjusted the Ph to 7.2 and brought the CYA up to 70 with a goal of 75, but overshot and CYA is now 100. FC is 23 and will not seem to go higher. I am scrubbing the entire pool twice daily for the last 5 days and have seen some progress but it has been slow. Question: Do I need to drain water to get CYA level down to 75 for a salt pool? I have ordered the salt test kit as I suspect the salt generator is not working properly. In treating the Black Algae in the past I have positioned tri-chlor pucks over the heaviest infestation. It appears now that the plaster has been displaced, and the bare concrete is showing through. Can these areas be patched with the white plaster or must the entire pool be resurfaced?
Black Algae, in the middle of my first SLAM
- Thread starter Jack P
- Start date
You can leave the CYA at 100, just raise the FC level accordingly, [FC/CYA][/FC/CYA]. The plaster can be patched or if the pool is not leaking it can be left as is for now
Thanks, I have been trying to get the FC to 28 when the CYA was 70 but the FC number has barely changed. Is this because the FC is being reduced as the Black Algae is being killed?? When I brush the pool, there is a grey cloud ahead of the brush head. Is this the dead algae??
Are you using PoolMath to dose the pool to your target from your current FC value? How much bleach is PoolMath suggesting to hit that target and how much are you adding?
I am using the Pool Math calculator,, my last dose was yesterday when I added 1-1/2 gallons of 12.5% pool chlorine. I began the process by adjusting the ph down to 7.2 and then began to ramp up the bleach and CYA. I apparently got to aggressive with the CYA in try to get to the 70-80 range for a SWG pool. It appears that it is progressing albeit slowly. I have begun to treat the black spots by rubbing the tri-chlor hockey pucks directly on the dark spots to see if that would move it along a little faster.
If you're fighting algae, you'll want to pay a lot of attention to the "Maintain" part of Shock, Level, and Maintain. Check before and after work, after dinner, and at bedtime and adjust the chlorine if it has fallen. Brush as much as possible, and you'll make faster progress.