Pool Closing-When to slam ?

[Fool4pool]

I have seen several pros here say they slam a few days before closing and let it drift down? Why?

Seems like slamming the day you close would have maximum benefit for the whole off season? So I'm curious about what I'm missing.

 

[Catanzaro]

I have seen several pros here say they slam a few days before closing and let it drift down? Why?Seems like slamming the day you close would have maximum benefit for the whole off season? So I'm curious about what I'm missing.

Slamming a few days before closing and allowing your levels to drift down is done with the optional Poly-Quat 60 at closing. There is an interaction between high chlorine levels and the algaecide that does not work. Even the instructions state to keep your FC at a certain level. Quite honestly, I have never read the instructions.

If you are not using the algaecide (Poly-Quat 60 only), then you can SLAM the pool, allow to drift down and then the day before bring up to SLAM again, run pump overnight and close in the AM.

- - - Updated - - -

Polyquat algaecides: Mode of Action

Post # 2 (Chem Geek), and I quote:

"Polyquat does not oxidize chlorine; it is the other way around where chlorine oxidizes Polyquat."

 

[Fool4pool]

Thanks, it is confusing though. So I would slam, even though it doesnt need to be slammed, drift fc down under 5ppm, then add polly 60? Not sure why I'm slamming if I have to bring it all the way down again. So then for 6 months it's just the alagaecide in there all winter and very little chlorine?

 

[Catanzaro]

Thanks, it is confusing though. So I would slam, even though it doesnt need to be slammed, drift fc down under 5ppm, then add polly 60? Not sure why I'm slamming if I have to bring it all the way down again. So then for 6 months it's just the alagaecide in there all winter and very little chlorine?

As I mentioned previously, high chlorine levels consume algaecide. No Poly-Quat, the levels do not need to be lowered. In addition, the only task you are accomplishing is to prevent algae from occurring until the temperatures drop significantly in the winter. Algae will not grow in cold weather. The key is also to open early as well in the spring as the algaecide and even if you have chlorine left will not last for 6-8 months, depending on long your pool is closed. Another key component is the cover you use (solid is always better than mesh).

 

[JoeRJGR]

I slam mine the morning before I close it...for the reason you stated...

 

[Fool4pool]

As I mentioned previously, high chlorine levels consume algaecide. No Poly-Quat, the levels do not need to be lowered. In addition, the only task you are accomplishing is to prevent algae from occurring until the temperatures drop significantly in the winter. Algae will not grow in cold weather. The key is also to open early as well in the spring as the algaecide and even if you have chlorine left will not last for 6-8 months, depending on long your pool is closed. Another key component is the cover you use (solid is always better than mesh).

Ok, but then I don't understand why I would slam at all if using algaecide 60. Why not just keep chlorine level low? I guess that's the part I don't get.

 

[Catanzaro]

Ok, but then I don't understand why I would slam at all if using algaecide 60. Why not just keep chlorine level low? I guess that's the part I don't get.

One does not necessarily have to bring levels up to SLAM, but it is extra insurance in cleaning up the pool right before the closing (Period). It is not set in stone either. If you want to keep your levels where they are and add the Poly 60, that is fine as well. There is no right or wrong way to do this, (only choices). Just make sure that you pass the overnight and your pool is free of debris, leaves, algae spots, etc. Everything should be in pristine condition prior to closing and this is why most of us usually recommend bringing the pool up to SLAM level approximately one week before, not adding any more chlorine and allowing levels to drop down to normal prior to adding Poly 60.

Just because you can not see algae, does not mean it is not there. Poly 60 will not kill algae, only prevent this, and the underlying reason why one last SLAM is performed prior (just in case).