Closing Water Balance Questions

[kllentini]

I’m prepping to close my pool this weekend here in Massachusetts. We’ve had alot of rain and we haven’t used the pool in a few weeks. I tested the water as part of my prep for closing and things seem off:

FC - 17.5
pH - 7.0
CYA - 90
Alkalinity - 60

The high FC caught my attention and I’m not sure how to explain that? I added the proper pH increaser to come up to like 7.5 before closing but it only came up to 7.2.

The pool is clear but I’m removing much more leaves, acorns and debris as we move toward the end of September.

This is is my first season and this will be first attempt at closing this coming. weekend. I’m concerned about this seeming lack of balance before closing. I know this is a vague question but does anyone have any suggestions to try this week?

Thanks

 

[mknauss]

How do you chlorinate?

With a CYA of 90, your FC is not all that high.

 

[duraleigh]

A low pH like that (but not too low, yet) indicates you may have been chlorinating with pucks. Any other chlorine you have been adding?

 

[Catanzaro]

The high FC caught my attention and I’m not sure how to explain that?

What does this mean?

 

[kllentini]

Thanks for input so far. My CYA was 55-60 range for most of season and I ran my FC about 6-8. I chlorinate with pucks in the skimmer basket and add 12.5% liquid when a shock needed after heavy weekend usage. The pool is very old with a single skimmer and single return line that isn’t the original return.

I guess I must’ve been adding too many pucks to get it up to 17.5 so I was surprised by that. When I checked the CYA level it was quite different from the consistent in season levels.

So I guess I just want to make sure that these levels aren’t prohibitive of closing the pool. I anticipate I can get the FC to drop a little before the weekend before I close and I also want to have the pH between 7.4 and 7.6. This was my first season and all the help here at TFP has been excellent. I just want to make sure my FC isn’t too high to close? And if so where about should it be before closing?

Thanks again.

 

[Catanzaro]

3" Tablets in the skimmer is a "NO NO". Very acidic and only ok if the pump is running 24/7. You can close the pool with high chlorine levels and you should consider switching over to liquid chlorine as well for next year.

 

[Mendy48]

Let you FC fall half way half way back to normal levels before closing your pool. In other words, you FC should be within range according to your CYA. View Recommended Chemical Levels. I'll be closing my pool for the first time myself, so this is new to me. I'm curious as to what others think to so I'll let other chime in first.

 

[Catanzaro]

Let you FC fall half way half way back to normal levels before closing your pool.

Your levels at closing are either at the highest or at normal, not in between. If you are using Poly-Quat, then you must allow your levels to come back down to normal. If you are not using the algaecide, then keep at SLAM right before you close. Please see link below about the algaecide.

If you are using Poly-Quat, allow your levels to drift down to your normal CYA/FC levels. If you are not using the algaecide, you can close with the SLAM - higher levels.

You can even bring to SLAM the day before you close as well. 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. Post # 2, quote from (Chem Geek)

Polyquat algaecides: Mode of Action