First time SLAM

chaser

0
Aug 12, 2012
6
New Jersey
Hello,
I am am running my first SLAM today. SWG has been maintaining FC at 1-2 with pump running 10hr/day (set to 95%). After a party with 30 or so swimmers in the pool, I decided it was time to SLAM. This is my first pool season (completed Oct '12) and water has always been crystal clear.

Prior to SLAM pH was ~7.5, CYA 50-60

After adding 7 lbs of Cal-hypo 65 shock the water became VERY cloudy -- can barely see floor of my 1ft sun shelf, let alone bottom!. After 6 hrs it is still VERY cloudy.

Test:
FC 26
CC 0
CH 300

Did I do something wrong?
Does it just take a long time to dissolve?

Running pump 24/7. Will check FC in a few hrs.

Do I need an intervention or patience?

Thank you in advance!
 
That is one reason we do not really recommend using cal-hypo. It should clear up eventually. Best to maintain the shock level with bleach.

Likely when you complete the SLAM process you should raise the CYA a little high and see if you can get the SWG to maintain a higher FC ... otherwise you need to increase the SWG output and/or pump run time ... or be supplementing with bleach every day.
 
Guess I should have used liquid chlorine. Arrrgggh!! That'll be the last time I listen to the pool store!
So it's the calcium thats making it cloudy? How long do you think we are we talking about?
Does this mean my CH will continue to rise as it dissolves?
By the way, is it safe to swim during SLAM?
 
As long as your FC level at at or below shock level for your CYA.

For my CYA for 40, I need to keep my FC above 3 at all times. I aim for 7 or 8 each day and a shock is 15FC. It is safe to swim as long as the water is clear and the FC is at or below 15FC.

Your "safe" levels will depend on your CYA.
 
We find it is rarely a good idea to listen to the pool store ;)

Likely it is the calcium that made it cloudy if it happened suddenly when you added it. No idea how long it will take to clear up.

Have you found poolcalculator.com yet? It will tell you what that the 7 pounds you add will 15ppm FC (odd that you are seeing 26???) and 11ppm of CH.

Are you planning to follow the SLAM process? [slam:2z3gfifh][/slam:2z3gfifh]

We say it is safe when the FC is less than shock level. While in the SLAM process, the Fc should be above shock level.
 
chaser said:
Hello,
I am am running my first SLAM today. SWG has been maintaining FC at 1-2 with pump running 10hr/day (set to 95%). After a party with 30 or so swimmers in the pool, I decided it was time to SLAM. This is my first pool season (completed Oct '12) and water has always been crystal clear.

Prior to SLAM pH was ~7.5, CYA 50-60

After adding 7 lbs of Cal-hypo 65 shock the water became VERY cloudy -- can barely see floor of my 1ft sun shelf, let alone bottom!. After 6 hrs it is still VERY cloudy.

Test:
FC 26
CC 0
CH 300

Did I do something wrong?
Does it just take a long time to dissolve?

Running pump 24/7. Will check FC in a few hrs.

Do I need an intervention or patience?

Thank you in advance!
Survey says Patience.

Besides cloudiness... you're also raising the CH level, which is fine up to a point, as you have a plaster pool. But besides the obvious risk of scaling, you also have a SWG, and Calcium can build up on the plates making it less efficient. It's best to avoid the powders from now on.
 
Did you turn off your SWG when you started to SLAM?

If i were in your shoes i don't think i would have SLAMed the pool after the party. I would have just raised FC levels a little with bleach. I would have also gave FC a little bump prior to the party.

You are also maintaining your chlorine level a little low, it needs to be at 3 PPM and never below for your CYA level. Sounds like after all this is done you need to either run your pump a few more hours or increase CYA levels.
 
YOu will almost never pass the OCLT on the first night. This process will require some time so you must be patient and stay on a steady even course. Your pool took quite a while to get in it's condition so it will take a few days to get it back right.

I suggest you wait until your water is crystal clear and your CC's are .5 ppm or less and then perform the OCLT.
 
This is kind of a special case ... there really was not an indicator that pointed to "requiring" the SLAM process. The FC was slightly low from the SWG but the water was clear with no CC, followed by heavy use and a decision to pre-emtively go through the SLAM process.

A confusion factor of using a LOT of cal-hypo to start the process resulted in cloudy water ... in this case the cloudiness may not be anything besides a reaction to the added calcium.

So, I actually would not be terribly surprised if the OCLT was passed on the first night since there was not actually any sign pointing to the need for the SLAM process in the first place. Although if the SWG was on, then the OCLT was invalid anyway.

Still, safest to maintain the shock FC level until the water is clear followed by a verification OCLT.
 

Enjoying this content?

Support TFP with a donation.

Give Support
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.