Shocking your pool is easy: Use a shock treatment to bring your 10 to 12 PPM. Then, wait a day or two for the chlorine to come down to its normal level, about 1.5 to 3.5 PPM. Pro tip: For best results, shock your pool a few days before you plan to shut it down.
Several days before closing, shock the pool with a chlorine shock or non-chlorine shock, using at least 2 lbs per 10,000 gallons (follow package directions). Allow the chlorine level to return to 1.0-3.0 ppm before adding any winter algaecide or your pool cover.
Chlorine shock can also damage floating pool covers, when installed immediately after shocking. If you use chlorine shock to close the pool, shock the pool 2-5 days before closing, or add stain and algaecide winter chemicals a few weeks later, under the cover.
Shocking kills any bacteria that might linger in your pool during the winter. We recommend shocking a few days before you close the pool. If that is not possible, make sure to shock the pool the night before you close it for winter.
Once you know where your pool chemistry stands, balance the water, adjusting the pH to 7.2 - 7.6, alkalinity between 80 and 120 ppm, and calcium hardness between 200 and 350 ppm. Shock your pool with Pool Breeze Granular Shock or 12.5% Liquid Shock two days prior to closing.
Closing a pool that is green with algae, or dirty with debris or with water that is unbalanced, leads to heavy staining and saturation of the water with dead algae cells, which makes it easier for subsequent generations to grow.
By simply adding algaecide to your water prior to closing, you can prevent algae growth from occurring during the cold, winter months which makes for an easier opening in the spring. You can apply algaecide directly to the pool water and allow the pump to continue to circulate for approximately two to four hours.
Add 1 gallon of shock per 10,000 gallons of pool water and 1 gallon of Winterizing Pool Chemical Agent per 15,000 gallons of pool water.
Super chlorinate with liquid chlorine or other chlorine source and add winterizing chemical kit to pool; allow filter to circulate to evenly distribute chemicals. (Use chemicals as labels indicate.) Use 1 gallon of liquid chlorine per 10,000 gallons of pool water.
Algaecide should be used after each shock treatment, so it has a better chance to support your chlorine as it works its magic. Be sure to shock your pool first, then when the chlorine levels of your pool return to normal, add the correct amount of algaecide to several places around your pool while your pump is running.
Pools can immediately turn green after shocking when they have metals like copper in the water. These metals oxidise when exposed to high levels of chlorine which makes the pool water turn green. Adding a metal control product such as Zodiac Metal Remover will help to restore the pool water.
If your pool has been green all season you're probably super excited to close it. While it seems like the easiest option – it's not! It's much smarter to close your pool as clean as possible. Algae can grow in water as cold as 50 degrees.
Pools open green when the winter cover is not keeping out debris, the water chemistry is poor, and there is inadequate sanitizer. Even if you open late, and even if you have a mesh safety cover – you can skip the stains and discoloration by avoiding these problems with the pool cover and the winter water chemistry.
It removes impurities and contaminants that could stain the pool or consume your winter water chemicals. If shocking with chlorine pool shock, add it 5-7 days before closing the pool, as very high chlorine levels can disrupt or destroy your winter algaecide or stain and scale chemicals.
You really only need one chemical (algaecide) to properly winterize a swimming pool. You need some other stuff to protect your pool from harsh winter conditions, but only one chemical to add when closing.
There are several saltwater pool closing kits on the market and most of them include the same things: an algaecide, stain-fighter or scale inhibitor, and an oxidizer. Use a closing kit to gain the benefits from these three products or purchase them separately–whatever works best for you and your pool.
People often avoid covering their pool for the winter because pool covers are an additional cost. However, an uncovered pool will cost you far more over the span of a few short years than a simple pool cover. For one thing, an uncovered pool will become a catch-all for leaves and debris.
Freezing temperatures
September and October are a good time to close the pool because the weather is ideal. It's still warm to be outside, enjoying the sun, even if you hate to say goodbye to summer. But once those temperatures start dropping significantly, you're going to kick yourself for not closing the pool sooner.
A pool filter should be run for a minimum of 6 hours after shocking a swimming pool. This is to allow the filter to clean the water and give the shock enough time to fully mix with the pool water. Running the filter after shocking for 24 hours to 7 days is necessary if the pool has a large amount of algae.