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Things You Need To Close Your Pool

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Winterizing A Swimming Pool
If you will be closing your own swimming pool this year then review the items on this page that you might need. Since you only close the pool once per year it can be easy to forget about the little items that you used up last year and never got around to replacing. Having these items on hand when you go to close the pool will help you to eliminate those last minute trips to busy local pool stores.

If you are looking for help about how to close a pool properly then you can watch my pool winterization video series as well as read this article about pool closing tips. If you have closed your pool before, or feel that you have everything well in hand already, then consider the consumable items on this page that you might need to get.

Pool Winterization Plugs

Pool winterization plugs are that item that just seems to get lost every year. If you have lost yours, or more commonly if yours are of questionable condition, then consider replacing them this year. These plugs perform an incredibly important function for your pool and their low cost is a pittance if it means improved protection of your pool. The last thing you want is to have a failure of your underground plumbing system due to a leak in a five dollar winterization plug.

The most common pool winterization plugs are rubber expansion plugs that are sized based on the size of the pipes you are plugging. Size 9 plugs are the most common plugs for 1.5" pipes that most pools have. Size 8 plugs are smaller but still suitable for some 1.5" pipe applications as well as most 1.25" pipe sizes like the ones that most above ground pools have. Size 10 plugs are most commonly used for 2" pipe sizes.

While this style of winterizing plugs are easy to use and fairly reliable they do have some limitations. One of the biggest concerns with these rubber plugs is that if the water level is at the height of the plugs when the surface freezes this can result in the ice grabbing the wing nut on the plug and can pull it out of the wall when the water level changes. This would be most commonly encountered with safety covers that allow water into the pool over the winter. On these pools I have stopped using rubber plugs like this where possible.

If you have threads on your pool returns then you should consider using this style of pool plugs. Once threaded in, provided you have correctly used a thread sealant, there is no chance that these plugs will fall out during the winter. While these plugs come with a rubber gasket O-ring I do not trust this to provide a water tight seal. Most commonly I would use Teflon tape for a pipe sealant. If you are not confident enough using Teflon tape then you can also use 100% silicone applied to the threads. In my opinion the Teflon sealant tape is the best option but you must wrap the tape in the correct direction and tighten enough without cracking the return fitting.

One of the new options for pool winterizing plugs are these duck plugs that are designed to allow you to blow out return lines while they are still underwater. This enables you to be able to safely winterize the plumbing lines without needing to drain your pool. While these plugs do work, and are great for applications where water conservation is a priority, these plugs are not as secure as other types of pool plugs. With careful use these can be used in situations where other types of pool plugs are just not an option.

Pool Skimmer Gizzmo

If you live in an area that experiences freeze and thaw cycles every year then you should be using a "gizzmo" in your skimmer. This product has 1.5" standard threads for most in ground and above ground swimming pool skimmers. Use a thread sealant before installing them. If you have a newer pool or a larger pool then your skimmer may have 2 inch ports. If this is the type of skimmer that you have then you will need to get the super gizzmo that is taller and has both 2 inch and 1.5 inch thread options.

In order for a gizzmo to protect your skimmer it needs to be water tight like a empty soda bottle with the lid screwed on. If you can squeeze your gizzmo and air escapes from it, or if you have any water trapped inside the gizzmo then this means that it has been compromised and is now garbage. Replacing a broken skimmer is an expensive project for any style of pool and the gizzmo is essentially your only line of defense. Broken skimmers from poor winterizing is one of the most common winter related pool failures.

An additional layer of protection that can use in your skimmer pipes as well as any pipes you are winterizing is this foam rope or "backer rod" which you can put into the pipes after you have blown out all of the water. In the event that you have a plug or gizmo failure then there is a chance that the foam rope in the pipes will prevent ice from expanding and pushing outwards on the pipes. Usually about 12 inches of foam rope into every pipe before you put in the plug is ideal.

Pool Antifreeze

Not every pool owner uses this however adding antifreeze to your pool lines can be very helpful in protecting against damage from freezing. Not usually used in return lines, this product is ideal for use in pool skimmers as well as automatic water filler canisters. After adding 500ml to the skimmer pipe then you would plug the skimmer as normal. Once the skimmer is plugged then add 1 to 2 liters to the skimmer directly. This will help to prevent any water that does find its way into your skimmer from freezing. Auto filler containers are winterized in a similar way. Once the fill water has been turned off and blown out, add 1 or 2 liters to the auto filler body.

Pool Cover Patches

If you have a mesh safety cover then it is a matter of time until you find a hole in the cover. These covers can snag when you drag them into place, or can puncture from falling trees and branches. Most commonly however they simply get holes chewed in them by mice. During the swimming season when your pool cover is in the bag and usually somewhere like a pool shed, they can become a comfortable home for rodents. Unfortunately the damage that they do is very extensive. Mice will tend to chew through the rolled up cover to get to the center. This results in small holes in many different sections of the cover. If this has happened to you then you can explore having repairs done by sending your cover back to the original manufacturer. If you are not inclined to go this route then a much less expensive option is to pick up some of these safety cover patches and apply them before you install the cover on the pool. For larger holes you can patch the hole on both sides of the cover for best results.

Pool Water Bags

If you have a tarp style pool cover then you will almost certainly need more water bags (again) this year. Going back many decades pools used to use sand bags instead of water bags as commonly used now. The problem with sand bags is they were a pain to store and even more of a pain to clean out of the pool if a bag ripped or fell in during the winter. The bad part about water bags for holding down your pool tarp in the winter is simply the fact that water bags break if look at them the wrong way. It is always a good idea to have a few extra water bags on hand for your pool to deal with "leakers" when you close and to replace dead bags that leak out in the days following closing your pool.

Pool Closing Chemicals

In addition to adding chlorine when you close your pool, or using a pool closing kit there are some less common chemicals that you may want to consider adding to your pool when you close for the winter. The closing kit contains chlorine (or non chlorine shock depending on which kit you buy) as well as a scale preventer and an algaecide. While this is sufficient for most pools there are some specific situations that might require additional chemical treatments.

Phosphates are a problem in many swimming pools and most pool owners may not even know about. Phosphate testing is not something that most water labs test for unless you specifically request it. At 500 parts per billion or higher phosphates will promote algae growth which will quickly deplete any chlorine reserve that is in the water once you put the cover on. If you have phosphates in your water then the chances of you opening your pool to green water next year is very high. While phosphate remover is one of the more expensive pool chemicals, there is no other solution to getting the phosphates out of your pool if you have them. Treat your pool for phosphates before it comes time to close the pool for the winter for best results.

If you have metals in your pool water then it is important to treat your pool for this before the winter season. using a high quality metal sequestering agent will prevent stains from iron, copper and other metals in your pool water. Have your pool water tested for metals prior to closing and if you have any then be sure to treat the pool before it comes time to close. If you have existing metal staining in your pool then this product will work to reverse the stain over the winter season.

Even if you choose not to use a closing kit you may find it beneficial to use a stain and scale control product like scale free. This product will work to prevent scale from developing in the pool as well as working to remove any existing scale that you might have. This product would be ideally be used in advance of when you intend to close the pool for the winter.

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