Quick answer<\/h2>\n
How to Close an Above Ground Pool: Step-by-Step Winter Guide: Quick answer To close an above ground pool, clean it, balance the water, add winter chemicals, lower the water 4-6 inches below the skimmer, disconnect and drain the pump and filter, plug the return and skimmer, add an.<\/p>\n<\/section>\n\n
There’s a bittersweet moment every fall when you realize it’s time to close your above ground pool. The good news? Spending 3-4 hours now saves you from a green, slimy nightmare come spring. Learning how to close an above ground pool<\/strong> properly isn’t complicated, but skipping steps or guessing on chemicals can turn a $5,000 pool into an expensive headache.<\/p>\n\n I’ve seen pool owners rush through closing weekend, only to spend $400+ on algae treatment and new equipment the following May. Don’t be that person. This guide walks you through every step, including the exact chemical calculations most articles skip over.<\/p>\n\n Most closing guides tell you to “add winterizing chemicals” without explaining how much. That’s like a recipe saying “add some flour.” Not helpful.<\/p>\n\n We calculated dosages for common above ground pool sizes using standard product concentrations. These numbers give you a starting point\u2014always check your specific product labels, since formulations vary between brands.<\/p>\n\n Methodology:<\/strong> Calculations are based on standard chemical dosing rates: pH increaser at 1.5 lbs per 10,000 gallons to raise pH by 0.2, alkalinity increaser at 1.5 lbs per 10,000 gallons to raise TA by 10 ppm, 60% polyquat algaecide at 16 oz per 10,000 gallons, and non-chlorine shock at 1 lb per 10,000 gallons. We assumed pools need moderate adjustments from typical end-of-season readings.<\/p>\n\n Limitations:<\/strong> Your actual needs depend on your current water chemistry, specific product strengths, and local water conditions. Test your water first, then adjust these recommendations accordingly.<\/p>\n\n | Pool Size (Gallons) | Current pH | pH Increaser Needed | Alkalinity Increaser (to raise 20 ppm) | 60% Polyquat Algaecide | Non-Chlorine Shock | Stain & Scale Preventer |<\/p>\n |———————|————|———————|—————————————-|————————|——————-|————————|<\/p>\n | 5,000 (12′ round) | 7.0 | 1.5 lbs | 1.5 lbs | 8 oz | 0.5 lbs | 8 oz |<\/p>\n | 7,500 (15′ round) | 7.2 | 1.1 lbs | 2.25 lbs | 12 oz | 0.75 lbs | 12 oz |<\/p>\n | 10,000 (18′ round) | 7.0 | 3 lbs | 3 lbs | 16 oz | 1 lb | 16 oz |<\/p>\n | 13,500 (24′ round) | 7.2 | 2 lbs | 4 lbs | 22 oz | 1.35 lbs | 22 oz |<\/p>\n | 18,000 (15’x30′ oval) | 7.0 | 5.4 lbs | 5.4 lbs | 29 oz | 1.8 lbs | 29 oz |<\/p>\n\n To calculate your pool’s volume:<\/strong> Round pools = diameter \u00d7 diameter \u00d7 depth \u00d7 5.9. Oval pools = length \u00d7 width \u00d7 depth \u00d7 5.9. If you want the fast version, use the Pool Chemical Calculator volume calculator<\/a>, then use the chlorine calculator<\/a>, pH calculator<\/a>, and alkalinity calculator<\/a> to dial in the closing dose.<\/p>\n\n The Pool Chemical Calculator app<\/a> keeps those calculations on your phone while you are standing next to the pool, which is exactly where you need them during closing.<\/p>\n\n Disclosure: As an Amazon Associate, Pool Chemical Calculator may earn from qualifying purchases.<\/p>\n\n Timing matters more than most people realize. Close too early, and algae grows under your cover during warm days. Close too late, and you’re wrestling with frozen equipment.<\/p>\n\n The sweet spot: when water temperature stays consistently below 65\u00b0F.<\/strong> For most of the U.S., that means late September through mid-October. In the South, you might wait until November. Up North, early September isn’t too soon.<\/p>\n\n Here’s the thing\u2014water temperature, not air temperature, is what matters. Algae goes dormant below 60\u00b0F. Close while it’s still warm, and you’re creating a greenhouse for algae under that cover.<\/p>\n\n Start here. Always. Unbalanced water spends all winter attacking your liner, corroding metal parts, and creating the perfect environment for spring algae blooms.<\/p>\n\n Target ranges for closing:<\/strong><\/p>\n A basic test kit like the Taylor K-2006 Complete Test Kit<\/a> gives you accurate readings. Those cheap test strips? They’ll get you in the ballpark, but you want precision before your pool sits untouched for 5-6 months.<\/p>\n\n If your pH is low (acidic), add pH increaser. If alkalinity is low, add alkalinity increaser first\u2014it affects pH, so address it before fine-tuning pH.<\/p>\n\n Debris doesn’t just sit there over winter. It decomposes, stains your liner, and feeds algae.<\/p>\n\n Your cleaning checklist:<\/strong><\/p>\n Pay extra attention to corners and around the ladder. That’s where organic matter loves to hide.<\/p>\n\n Order matters because some chemicals react with each other. Add them wrong, and you’ve wasted money and potentially created a chemical mess.<\/p>\n\n The correct sequence:<\/strong><\/p>\n\n Don’t add all chemicals at once. Shocking and algaecide in particular need separation time.<\/p>\n\n This step confuses a lot of people. You need water low enough to protect equipment but high enough to support your cover and liner.<\/p>\n\n Lower the water 4-6 inches below the skimmer opening.<\/strong> That’s it. Going lower risks your cover falling in and stressing the liner.<\/p>\n\n Some people drain below the return jets too. This depends on your setup\u2014if your return jets are close to skimmer height, draining below the skimmer handles both.<\/p>\n\n Use your pump to lower water, or rent a submersible pump if your filter pump isn’t suited for the task.<\/p>\n\n Water freezes. Ice expands. Expansion cracks pumps, filters, heaters, and chlorinators. It’s physics, and physics doesn’t care how much your equipment cost.<\/p>\n\n Pump and filter:<\/strong><\/p>\n Ladder and accessories:<\/strong><\/p>\n Heater (if applicable):<\/strong><\/p>\n For cartridge filters, remove the cartridge, clean it with filter cleaner, let it dry completely, and store it flat. A wet cartridge stored in a cold garage becomes a moldy cartridge.<\/p>\n\n Freezing water in these lines can crack plastic fittings and damage your pool wall.<\/p>\n\n For the skimmer:<\/strong><\/p>\n For return jets:<\/strong><\/p>\n If you’re in an area with brutal winters (I’m looking at you, Minnesota), some people blow out the lines with a shop vac first. But for most above ground pools with short, simple plumbing, proper draining and plugging does the job.<\/p>\n\n Yes, you need one. The air pillow sits in the center of your pool and serves two purposes:<\/p>\n\n Inflate it to about 60-80% capacity. Over-inflating increases the chance it pops from cold-weather pressure. Under-inflating defeats the purpose.<\/p>\n\n Position it in the center using string tied to opposite sides of the pool wall. Some people use two smaller pillows for larger pools.<\/p>\n\nWhat We Analyzed: Winterizing Chemical Dosage Calculations<\/h2>\n\n
Above Ground Pool Closing Supplies<\/h2>\n\n
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<\/a>When Should You Close Your Above Ground Pool?<\/h2>\n\n
Step-by-Step: Closing Your Above Ground Pool<\/h2>\n\n
Step 1: Test and Balance Your Water Chemistry<\/h3>\n\n
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Step 2: Clean Everything Thoroughly<\/h3>\n\n
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Step 3: Add Winterizing Chemicals in the Correct Order<\/h3>\n\n
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Step 4: Lower the Water Level<\/h3>\n\n
Step 5: Drain and Store Equipment<\/h3>\n\n
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Step 6: Protect Your Skimmer and Return Lines<\/h3>\n\n
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Step 7: Install Your Air Pillow<\/h3>\n\n
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