Do I need to SLAM

[Ian196499]

Hi

I foolishly allowed my FC to drop to 0.3 for a day and noticed a few small lines of green / yellow algae in the grout at the bottom of the tiled pool.

I have raised the FC back up and scrubbed the pool and the water has been clear for 24 hours.

My test results ( K2006) are:-

FC3.5
CC 0.2
TA 104
CH 240
cYA 26 ( note we have an enclosure over the pool so we don’t lose FC to sunlight)

Do I need to slam anyway given I got some algae? I read somewhere that you can’t always see algae and I don’t want to risk that there is some there.

Thanks !
Ian

 

[cfherrman]

If you have a question on slamming you can just slam, it will be easy and quick if you didn't need to.

Call your cya 30

 

[Richard320]

Algae doesn't just appear overnight. You probably had a low-level infestation for days or weeks that suddenly bloomed and became visible. Now you've beaten it back into invisibility but it is probably still lurking. My advice is to SLAM. If you don't need it, you'll pass the Overnight Chlorine Loss Test the first night. If you did need it, you got a head start on it.

 

[woodyp]

I would SLAM. I seriously doubt you got that little dab of misfortune over the course of one day. 24 hours might do you.

 

[Ian196499]

Thanks - that makes sense and I will do a SLAM. It will be my first!

Of course, this has happened whilst we’ve got visitors who want to use the pool.
Would it be dangerous to wait 48 hours until they leave to do the SLAM provided there is no visible algae or should I not take that risk?

Thanks for the help!

Algae doesn't just appear overnight. You probably had a low-level infestation for days or weeks that suddenly bloomed and became visible. Now you've beaten it back into invisibility but it is probably still lurking. My advice is to SLAM. If you don't need it, you'll pass the Overnight Chlorine Loss Test the first night. If you did need it, you got a head start on it.

Thanks for explaining that Richard.

Worrying to know it’s been building for a while ?

I’m starting the SLAM today!

Cheers
Ian

 

[cfherrman]

Just do a sub slam at 30% cya, it's safe and they won't notice, then when they leave do full slam.

 

[Ian196499]

Just do a sub slam at 30% cya, it's safe and they won't notice, then when they leave do full slam.

Thanks!

Please forgive my lack of knowledge but what is a sub-slam?

 

[mknauss]

A full SLAM is going to 40% of CYA for your FC, or for you, 12 ppm FC. Just take your FC to 9 or 10 while you wish to use the pool. You may find the FC drops pretty quickly if algae is in the system. Test every couple hours and add back to the 9 or 10 FC.

When everyone is gone, take the FC to 12 ppm.

 

[splashpad]

Thanks!

Please forgive my lack of knowledge but what is a sub-slam?

You can swim up to the high FC level for your CYA FC/CYA Levels

 

[Ian196499]

You can swim up to the high FC level for your CYA FC/CYA Levels

Ok! Got it!

Thanks everyone for the help!

Ian