SLAM going well but have questions

[apv]

Have been doing SLAM. Cleaned my DE filter yesterday too and got a bunch of algae-gunk out. Pool is looking a lot better.

Questions for you experienced folks:

So I keep adding (liquid) chlorine to maintain my FC level until the overnight test shows a drop of 1.0 ppm per less -- meaning for me, that would be FC 16 to FC 15.

1) What if the drops are still in the range of 5.0? Could that mean I am not even hitting my FC target level?

2) Also, what level of FC should I maintain post SLAM? This article* says FC should be 7.5% of CYA -- so for me, CYA = 40, means that FC should be 3.0. Does that sound right?

3) Lastly, I have some algae on the walls that seems resistant to brushing? Mustard algae? How to diagnosis?

Thanks

*New Thinking: Chlorine/Cyanuric Acid In Balance - AQUA Magazine (Link removed - TFP Mod)

 

[mknauss]

1. Not sure what you are describing.
2. You follow FC/CYA Levels and stay in the Target range for your CYA.
3. Are you sure it is algae? If it will not brush off, then it may be metal stains.

The first criteria for a successful SLAM is crystal clear water. Only then do a OCLT.

 

[apv]

WRT #1 -- I am describing the changes in FC in ppm. Last night I measured it at 16 (my target), and then this morning, it was at 11.

So keep bringing it back up to 16 every day?

WRT #2 - so keep it between 5-7 @ CYA of 40 -- what's the highest you would allow kids to swim in it? My kids and wife are begging me to let them swim.

WRT #3 -- I will double-check but yes, I believe it is algae.

Water is super clear now.

 

[mknauss]

You should be maintaining your SLAM level FC by testing and adding liquid chlorine as often as possible. Every couple hours to start and then 3 or 4 times per day once the FC holds better. Read SLAM Process

You can safely swim in a pool as long as the FC is above the minimum and at or below SLAM level based on your CYA. You must also be able to see the bottom of the pool in the deep end of the pool.

If algae, your water is not clear. Keep SLAM and brush that area often.

 

[apv]

Got it. Will continue on SLAM path.

 

[apv]

You can safely swim in a pool as long as the FC is above the minimum and at or below SLAM level based on your CYA. You must also be able to see the bottom of the pool in the deep end of the pool.

So swimming intermittently during SLAM (assuming the FC level is below shock target) is okay?

 

[mknauss]

Sure. At SLAM level is OK -- I would suggest not wearing your designer swim clothes but I doubt there will be any effect.

Only real caveat is pH. If someone gets irritated eyes, it is because the pH is out of range.

 

[apv]

Got it. Thanks. My kids and wife will be appreciative.

In theory, the pH is at 7.5 -- we'll see what it is once we are done with SLAM.