The most important factor though is the size of the pool. You'll need about 52-104 oz of liquid chlorine per 10,000 gallons of water. This amount should get the chlorine level to between 5 and 10 ppm.
(Use chemicals as labels indicate.) Use 1 gallon of liquid chlorine per 10,000 gallons of pool water. Clean liner above the water line with Swimway Tile & Vinyl Cleaner or another product.
Often, it will look something like this. 12.5% Liquid Chlorine Pool Shock – Normal Dosage: 1 gallon of shock per 10,000 gallons of water. Shock Dosage: 2 gallons of shock per 10,000 gallons of water. Source: Champion Liquid Pool Shock instructions.
If you use chlorine shock to close the pool, it's best to do so about a week before closing. A very high chlorine level can harm your cover and destroy your algaecide.
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.
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.
Liquid chlorine and granular shock have the same active chemical that sanitizes your pool, what changes is the strength and the way you use it. Liquid chlorine is less costly, unstabilized and comes in liquid form. Granular shock is stabilized and comes in a solid form that dissolves in your pool.
To superchlorinate, add AT LEAST 2.5 ounces (5 tablespoons, 75 grams) of chlorine for every 100 gallons (400 litres) of spa water or part thereof. Adding more is fine and never a bad idea.
Unhook the filter hoses, and store all pool supplies indoors for the winter. 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. Spread swimming pool covers for above ground pools over pool and secure cable around the perimeter.
At an average of $0.004 per gallon, city water is the most inexpensive and most popular option. For 15,000 to 30,000 gallons, you'll pay between $60 and $120.
Once water is removed (and subsequently, the interior hydrostatic pressure), if there's an influx of groundwater, it will push the pool up and out of place. As a general rule, you shouldn't keep any pool empty for longer than it needs to be. Get the work done that you needed to do and refill it as soon as possible.
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.
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.
Closing a pool with leaves or acorns in the bottom will likely lead to a stained pool bottom. Winterizing the Equipment and Piping-It is imperative that the equipment be properly winterized. Failing to winterize the pump and filter will likely lead to freeze damage resulting in costly repairs.
You do not need a pool winterizing kit. Weird first sentence for this article, but it's true. 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.