Spring Swim Opening... started with cloudy water... SLAM

joetristano · Mar 23, 2021

Hi
It may be a nice weekend here in SC so I started "opening" my 15k gal in ground, SWG, pool last weekend. I dont do anything to "close" the pool other than clear the leaves as they drop late fall to prevent a big bloom in the spring. My pump runs a few hours a day in the winter in addition to its low temperature mode.

I wanted to open 2 weeks ago but wasn't able to so last weekend the water was a bit cloudy. Here's what I did (while running the pool robot alot with fine filters):

FC - 0
CYA - 0
Ph ~7.2-7.4
NaCl -2300

1. Cleaned pool of all debris + basket + backwash
2. Added some salt that I had - (need to get some more) -
3. Started slamming with CalHypo (It's tough to get enough bleach in large enough jugs with pandemic)
4. Last night was still a bit cloudy (I could see the bottom 7.5 feet down) so I shocked w/ 4 bags of 56% CalHypo - brought FC way up ~56 (~6:30 PM)
5. This morning water was crystal clear FC ~40 (~7:30 AM)
6. Water still clear, overcast day, FC ~24 (~3:30 PM) - SWG is NOT running

My question is , the water is clear, FC is still super high, do I need to add more shock or just wait for it to come down on it's own so the kids can swim this weekend? Then turn SWG on?

Thanks
Joe

ajw22 · Mar 23, 2021

Have you added any stabilizer?

With CYA 0 and FC of 24 the chlorine is too high to be safe to swim.

Add stabilizer to get your CYA over 60 and then the chlorine level will be safe to swim in.

What SWG do you have?

Please create your signature with details of your pool and equipment.

Newdude · Mar 23, 2021

On top of the CYA that Allen recommended above, you need to pass the Overnight Chlorine Loss Test and have a CC less than 1 to ‘be done’.

Don’t attempt it until the FC is 20. In the low 20s or above it degrades on its own possibly making you fail the Overnight Chlorine Loss Test

ajw22 · Mar 23, 2021

You can swim while doing the SLAM Process as long as the FC is slightly below SLAM FC level for your CYA level. After the swim is over then increase the FC back to SLAM FC level.

joetristano · Mar 24, 2021

ajw22 said:
Have you added any stabilizer?

With CYA 0 and FC of 24 the chlorine is too high to be safe to swim.

Add stabilizer to get your CYA over 60 and then the chlorine level will be safe to swim in.

What SWG do you have?

Please create your signature with details of your pool and equipment.

Hi Allen, thanks for the info. I have a Hayward Aquarite w/ a TCELL925 in it - Sand filter + Gas heater, Vinyl

joetristano · Mar 24, 2021

Thank you all for the help and insights. I'm adding stabilizer now and ready to go on to the next step

Thanks
Joe

joetristano · Mar 24, 2021

The disappearing dot is a tough test. I needed my teenagers to help read it. Doing that the CYA is between 60-80 depending on who saw the dot last. My FC is around 8 about an hour before sunset - no sun on the pool.

Another side question/comment- I had not realized that the aquarite displays 24 hour average and wondered why adding salt did not register. So I saw Jason’s post and recalibrated. Unfortunately, It’s a bit high at 3500 now. Some rain should bring it down?? Long story short, I’m very thankful for this forum.

As I learn more about the counter play between cya, cl and think about the overnight fc test, it makes me wonder about timing of my pump at night. I used to have it run from 6am to 10pm but now I’m thinking to have it run from sunrise to last light and give a boost if we swim at night. Does that make sense? Then find the right setting for what percentage to run the swg at?
Thanks
Joe

ajw22 · Mar 24, 2021

You lose chlorine during the day due to the suns UV therefore I like to generate my chlorine and replace it during the day. It keeps a more stable FC level over the day.

Never rely on the Aquarite salt reading. It diverges from the actual salt as the cell ages. You need to use the Taylor K-1766 Salt Test to determine actual salinity.

Also high salt levels cause the Aquarite components and board to overheat and burn out components and solder joints. Best to run it at the low end of the range from 2800-3000 ppm.

Hayward Aquarite SWG - Further Reading

www.troublefreepool.com