Closing Pool Months Before Freezing

[bigfreddy2000]

First time poster to this forum, but I've had a pool for about 10 years, with the same problem every year, so I thought I'd reach out for help.

I live in Minnesota, and I typically close our 12k gal pool shortly after Labor Day. It's been a warm fall, so I've kept it open and still have it open. I do close my pool myself. When I first bought the house, I just used those pool closing kits and followed the instructions (as well as the standard closing procedure of blowing out the lines and adding anti-freeze and removing eyelets and skimmer baskets and such), but every spring, the water is completely green and full of algae. I've since tried SLAMing the pool and have had the same results. It freezes here at various times each year, but typically doesn't freeze until late October into November, so the pool is sitting for 2-3 months before freezing occurs.

I'm thinking that with it sitting unfrozen and not circulating water for that amount of time, it allows the algae to build up before freezing, so it's a pain to get the pool clear in the spring and I need to go through A LOT of shock. Any tips for someone in my position where freezing occurs months after pool closing to make it easier in the spring? I'm hoping with closing the pool later this year, that will help, but on most years, the pool's been closed for a month now. I don't want to over-shock the pool and bleach the liner. I also don't want to keep the pool open this late every year since we don't use it and I'd spend more on chemicals keeping it open than the amount of shock I use every spring. Any tips would be greatly appreciated!

 

[JJ_Tex]

I'm probably the last person to give advice on closing, but I see lots of guidance to close based on water temp and not the calendar. Post up your water temperature and that may help others guide you.

 

[Mdragger88]

Sounds like your fc is falling too low while the pool is closed.
As JJ referenced the water temp is an important part.
We recommend winterizing after the water temp is low 60’s & falling. & opening before the water temperature rises much above 60.

I personally don’t like fighting the leaves etc so I cover my pool at the end of September/early October but keep it operating and chlorinating on a reduced schedule until the water is cold enough then I raise fc to slam level and winterize. Usually around Halloween.
I do the opposite of this dance in the spring. The pool is operating for about a month before I take the cover off. It’s usually early April here when the water temp starts climbing above 60 so chlorination must ensue but the sky is still falling lol
When I check my levels upon de winterization my fc is always at least in target range.
It takes me a couple minutes to peel the cover back a little and check things or add liquid chlorine.
I also like breaking up the work of closing and opening- less stressful.

 

[Mdragger88]

I usually take some fc samples around Christmas (we tend to get a little heatwave) & in late February/early March after the thaw but I have never needed to add fc, although if I did, I’d have caught it early and it would take a 5 minute lc add vs dealing with a long slam in April.
I have a robot so I can just throw him in to help mix things up - some folks use a submersible pump for this.

 

[bigfreddy2000]

Sounds like your fc is falling too low while the pool is closed.
As JJ referenced the water temp is an important part.
We recommend winterizing after the water temp is low 60’s & falling. & opening before the water temperature rises much above 60.

I personally don’t like fighting the leaves etc so I cover my pool at the end of September/early October but keep it operating and chlorinating on a reduced schedule until the water is cold enough then I raise fc to slam level and winterize. Usually around Halloween.
I do the opposite of this dance in the spring. The pool is operating for about a month before I take the cover off. It’s usually early April here when the water temp starts climbing above 60 so chlorination must ensue but the sky is still falling lol
When I check my levels upon de winterization my fc is always at least in target range.
It takes me a couple minutes to peel the cover back a little and check things or add liquid chlorine.
I also like breaking up the work of closing and opening- less stressful.

Thank you, this is very helpful!

It's been dropping to the low 40's here at night lately, so I've been running the heater at a lower temp just in case it drops even lower because I don't want to risk anything freezing up and then have a solar cover on to keep the heat in during the day. Then during the day it's been strange this year and has a high of 60 one day and then 80 the next. So I'm not sure what my water temp is without running the heater, but I'm sure it would be around 60-65 without running the heater and without the solar cover.

I think this is a good method. I always thought that running my pool extra would cost me more money, but when I step back and think about it, I've historically spent $50 or so on the "closing chemicals", which did nothing, and then another $50 on the "opening chemicals" which seemed to do nothing either, as I've had to go through a 4 bag shock treatment 3 times (12 bags) to clear up my pool in the spring. So that's an extra $150-$175 I've spend historically on the pointless opening and closing chemical kits and the shock, whereas I could just drain the water to winterization levels and run chemicals through my main drain so there's less water to treat and keep it running longer. I'll try that this year and hopefully it will come out better in the spring.

Being in Minnesota, I never really get the winter thaw you mention. People are still ice fishing on the lakes at that time, but I will keep in mind to open it sooner to check the levels and add chemicals sooner too, as I think that might help. I also have a robotic vacuum as well, so that will help spread everything around. Thank you for your help! Hopefully it helps out in the spring and I'm not waiting a week after I take the cover off just to use the pool and spending so much money getting it ready!