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Frequently Asked Questions About Pool Closing

Frequently Asked Questions About Pool Closing

21st Sep 2016

In cooler climates, the time to begin thinking about closing and winterizing your pool is upon us. The weather is getting more brisk, the leaves are changing color, and the warm memories of summertime fun are behind us. This is not usually the time of year that people like to think about their swimming pools, however, this is the most crucial time to pay attention to your pool to avoid unnecessary problems and costly repairs come springtime. Many pool owners go through the motions of this process without knowing the reasons behind many of the tasks. Below, we've listed several answers to some of the most frequently asked questions.

In-ground Swimming Pool With Ladder


What kind of chemicals do you put in the pool?

Most experts suggest the use of a concentrated shock treatment along with a winter algaecide and stain treatment product. Also make sure you adjust the pH and alkalinity of the water.


Do you put antifreeze in the pipes?

No, you should not have to. The only way that you can guarantee that your underground pipes don’t freeze is to force all the water out of the pipes with an air compressor or shop vac. The only time you would need to add anti-freeze is if you were going to leave water in the pipes. Then you would have to add it to keep them from freezing - but this is not recommended.


Do you drop, lower, or remove the lights?

No you do not need to adjust the lights in any way. Years ago, before people used compressors or shop vacs to blow the water out of the pipes, they had to lower the water in the pool down past the returns. Then they would remove the lights and drop them to the bottom of the pool because if the pool water froze, it might expand and actually crack the lights. More recently, since you can use the compressor to blow out the pipes, you can keep the water level in the pool higher up. There is much less of a chance that the lights will develop a leak if you just leave them as is.


Why do you have to lower the water in the pool if the pool has tile around the top at the water level?

If you have tile, and you do not lower the water level, when water freezes, it can expand outwards and actually crack the tile.


Do you have to lower the water for a vinyl liner in an in ground pool?

The only time that a pool needs to have the water lowered is if you have a gunite or cement pool with tile around the top. If you have a liner in the pool, then there is no need to lower the water level. When you use an air compressor to blow the water out of the pipes, and plug the return jets and skimmers, there is no need to lower the water. As long as you use those big plugs for the skimmers, you can keep the water at the regular level. The higher you can keep the water in the pool, the better it is for your pool cover and there will be much less of a chance of the cover falling in.


What if I prefer to lower the water level?

Basically it’s your pool, and if you are more comfortable lowering the water level, then by all means do it. Be sure, however, to still follow the procedures listed above for blowing the water out of the pipes as well.


Should I acid wash my DE filter before closing?

You should at least backwash it out before you close it down. This ensures that all the debris and old DE is out of the filter. If you want to have the filter "acid washed", that’s usually something you do at the pool opening. You don’t want to have the filter cleaned and then have it sit for the next six months with acid residue in it. Most people want to have it cleaned out right before they start up the pool in the spring. It is best to wait until then.


Should I vacuum the pool before I close it?

This is entirely up to you. We do not recommend closing the pool if there is a LOT of debris in it and in that case you should vacuum it all out, however, a few leaves and bugs are OK. Most people vacuum the pool right after they open it in the Spring anyway. If your area has a bad winter and part of your cover falls in the pool, you will just have to vacuum it again when you open it, so most people would rather just do it in the spring and only have to do it once.