Swimming pools don’t need as much care during the off-season, but that doesn’t mean you should completely ignore them. You can extend the swimming season if you have a pool heater, but you should consider closing your pool as soon as it gets too cold to swim. Here are some winter pool care tips to keep your swimming pool in great shape until your next opening.
Add Algaecide and Chlorine
Extra algaecide and chlorine, in appropriate amounts, are essential to help prevent the buildup of threats in your pool while the water is stagnant for a few months. The exact amount to use depends on the product, and you should always follow the manufacturer’s directions, but about one quart of a good algaecide is enough for a 20,000-gallon pool over the winter.
This is perhaps the most important thing to do when caring for your off-season pool. Even better, you can do this at the start of the off-season, so you don’t have to worry about it the rest of the time.
However, don’t rely exclusively on algaecide and ignore your pool. It’s still good to look at your pool every week or two to be sure it’s still clean. If you spot any algae growth in your pool, add more algaecide and clean your pool as soon as possible to prevent stains and damage.
Chlorine serves the same role here.
Drain your System to Prevent Freezing
Specifically, you should drain your pool water about six inches below your skimmer system. This gives some room for rainwater to seep in and raise your pool’s level without the hassle of having to drain and eventually refill the entire pool. The most important thing here is ensuring that all pipes and systems are protected from growing ice.
The exact steps depend on the pool you have, so we can’t give a universal guide for preparing systems. However, keeping the water level below your skimmer and jets generally ensures you can avoid too much damage.
Do not completely drain your pool. The water that’s still in the pool helps protect the interior liner and provides a safe, constant pressure. Don’t forget to empty the lines, remove them if possible, and let them dry before you begin storing them.
Keep your Pool Cover Clean and Remove Debris
The importance of this step depends on where you live. Assuming you’re using a pool cover (if not, read my guide on the best winter pool covers), keeping it clear of debris helps avoid damage and protects your pool cover. Sharp objects could damage weaker pool liners, while the weight can drag the liner itself down.
This isn’t as important if you have a thick pool liner. These tend to stay in place by virtue of size and weight, so debris doesn’t hurt them as much. However, letting leaves, rocks, branches, and other items weigh down the liner can still discolor over time.
Cleaning it regularly is a smart move, regardless of the type of cover you’re using. Make sure to pay attention to which chemicals you’re using and where they’re going. Remove snow from your winter cover, clean off stagnant water, and use your rake to remove debris rather than wash the pool liner. Water may get into the pool itself and alter the chemistry more than you want it to.
Use an air pillow to help keep snow off your cover and prevent it from bowing in too much.
Make Sure your Pool Cover Has a Snug Fit
Ensuring your winter pool cover has a snug fit around the entire pool is also vital for keeping things safe during the off-season. This is probably the trickiest part of caring for a pool during the off-season.
The main issue here is the pool shape. Rectangular pool liners are easy to find in almost any size you can imagine. This is especially true for thinner liners, but even thick liners that go across a pool are available online and in some stores.
Oval and irregularly-shaped pools, in contrast, are much harder to get high-quality liners for. A good liner goes entirely across the pool and slightly up the sides, with no more than a small amount of creasing as needed. Good liners can also go around ladders and similar extensions without compromising your overall function.
You want a fit that’s as snug as possible, but it’s hard for manufacturers to predict every sizing choice pools may have. Accordingly, you might need to buy a custom pool cover specifically for your pool. This is usually better than trying to find a cover for an irregular pool.
A second consideration here is determining how sturdy you want the cover to be. Basic liners don’t offer much support, but robust liners can be durable enough to walk on top of. These provide added safety during the off-season while fitting a pool snugly enough to be helpful.
Don’t forget to find a dedicated storage area for your pool liner. Keeping it clean, dry, and away from sunlight when it’s not in use will help you avoid rips and tears that could cascade into a bigger problem later on.
Use Enzyme Chemicals
Enzymes are helpful molecules when you’re trying to manage a pool. Although perhaps best-known for their functions within the body, enzymes are also handy in pools because they can break apart many organic molecules and ultimately convert them into carbon dioxide.
The result is a gas that bubbles away after using the chemicals. Chlorine can do the same thing, but it’s much worse than specialist enzymes. Worse, using chlorine reduces the amount in your pool, which is bad for maintaining proper pool chemistry.
You should use enzymes as often as the manufacturer recommends for the off-season, which is usually monthly. You can often use fewer enzymes during winter because the lack of use and the cover on top mean you don’t have many organic chemicals entering the pool once you close.
Use a Winterizing Kit
A winterizing kit is a complete set of chemicals for closing a pool. High-quality kits usually address most of the other items on this list, including oxidizing chemicals (either a replacement for enzymes or as enzymes), algaecide, and sometimes other chemicals.
Remember to follow the instructions for the winterizing kit exactly. This can include managing the water temperature or giving gases time to bubble off and escape before putting your pool cover on. Failing to follow the directions could damage your pool liner, pipes, or other systems.
Also, make sure your winterizing kit matches the type of pool you own. For example, adding too much chlorine through a winterizing kit could damage some types of pools. If you’re uncertain which types of winterizing kits work for you, talk to your pool’s installers or the staff at a local specialty store.
If you have a saltwater pool, the winterizing process is slightly different. Read my article on how to close a saltwater pool for the season for more.
Get My Free Pool Care Checklist
Download my free, printable pool maintenance checklist to help you accomplish regular pool care tasks for any type of swimming pool.
Open Your Pool Early
Finally, the best way to care for your pool is to open your swimming pool as early as you can. Even the best off-season kits only last a few months at most. If you’re ignoring your pool for too long, you could miss vital changes in the water chemistry. The best way to resolve this is to open your pool as soon as the weather permits.
Once your pool is open, you can rebalance all the chemicals and avoid any problems that may spring up due to other chemicals lingering in your pool for too long. Most pools are safest when they’re open and have the right chemistry, so this is a rare case where it’s better to use a product actively instead of avoiding it to try and reduce wear and tear.
Questions about winter maintenance? Let me know; always happy to help protect your pool during the winter months.