Vacuum, brush the walls if necessary, and remove debris from water. The pool will open more easily in the spring if it is clean when closed. Debris left in the pool over the winter may cause staining.
If you have a sand filter, backwash to clean the sand for next season. You can also use a product such as Filter Magic to aid in the cleaning.
If you have a DE filter, empty the DE and spray the fingers or grids with a cleaning solution.
If you have a cartridge filter, spray it with a cleaning solution
2)Lower the water level
Drop the water level of the pool to the bottom of the skimmer. If you use a safety pool cover, drop the water to 18 inches below the top of the pool.
3)Drain equipment
Remove the drain plugs on the filter and heater and allow them to drain completely.
4)Blow out the underground lines and plug return outlets
Using a strong pool vacuum, blow standing water out of the lines:
Remove the cover to the pump strainer housing and insert the pool vacuum exhaust hose. Close the valve so that the air is directed to the skimmer
When you turn the vacuum on, you should see water being forced out of the skimmer. Proceed from one skimmer to the next; while skimmer is blowing insert a gizzmo or plug into the skimmer/return openings.
Blow out the line to the main drain and turn valve to Channel Lock Air.
NOTE: After closing off the line, the pool vacuum motor should become more labored. This assures that the line is properly sealed.
Optional: Add pool anti-freeze to the lines. DO NOT use automobile antifreeze.
5) Add winterizing chemicals with a winterizing pool kit
Add 1 gallon of shock pool chemicals per 10,000 gallons of pool water and 1 gallon of Splash Winterizing Pool Kit Agent per 15,000 gallons of pool water.
6) Cover the pool
Spread pool cover for inground pool over pool and anchor with water tubes. Water tubes should be filled to 2/3 capacity. Do not stretch it taut, it is intended to dip in the middle, unless you have a pool safety cover, which should be pulled tightly and hooked to brass anchors around the pool.
RECOMMENDED: Purchase a durable pool cover pump to remove water from the winter pool covers. If water is allowed to build up it will stress the cover; if it freezes it may cause rips in the inground pool cover. Little Giant is a good choice.
Optional:
Purchase a Leaf Net and spread it over the winter pool cover. This will catch leaves and other debris and prevent them from building up on the cover. Every few weeks in the fall simply peel it off and shake debris loose.
Inflate an air pillow and float it on the water under the pool blanket cover. Air pillows facilitate the removal of water from the cover.
