How To Prepare (Shut Down) Your Unheated Swimming Pool in Victoria for the Winter Months

Introduction

Obviously we don’t live in the tropics, so as the warm months of summer draw to a close in Victoria. If your swimming pool in unheated and you don’t plan on swimming again for 6 months or more, it's probably time to start thinking about preparing your swimming pool for the winter months. Winterizing your pool properly can save you time, effort, and money; when it comes to reopening it again in the spring. This article will guide you through the process of putting your swimming pool ‘to sleep’ as it were, with specific tips and advice for pool owners in Victoria, Australia.

When Is the Right Time To Winterise?

Knowing when to winterize your pool in Victoria is important. Closing your pool too early can result in algae growth and expensive clean-ups. Leave it too late and your pool can become over-chlorinated, potentially damaging expensive equipment (for non-probed systems). The optimal time to start this process is often when the water temperature consistently stays below 15°C during the day. This is usually around late April to early May.

That said, making a slower transition can often be the answer to ‘getting it right’. It may not be summer any more, but it may not be winter yet either.

What To Do During the In-Between Months (Autumn/Spring).

Most pool owners want to go from summer mode, straight to winter mode, when in reality the weather and environment don’t do that, so why should our pools be trying to perform like that’s what’s happening?

Chlorine Levels

Chlorine levels need to remain similar throughout summer and winter months, however during winter, the sun no longer burns off chlorine the same way as it does during summer. Meaning your chlorine (production from salt chlorinators or manually added) requirements are a fraction on that during summer. Without sun burn-ff or people jumping in

Pool Covers

If you cover your pool during winter but not summer, then it’s important to note the chlorine required may be even further reduced. With less sun reaching the water and less debris falling in to cause contamination.

Water Circulation

Water circulation is the single most important factor to maintaining health water. No one would drink from a stagnant puddle, but a flowing stream is a very different story. During summer it’s ideal to rotate the entire water volume of your pool twice, every single day.

Example:

Imagine you had a 60,000 Litre pool.
Your pump pushed 6000 Litres per hour (100 Litres per minute).
Meaning your pool water would rotate once completely in 10 hours.
Therefor in summer you would ideally run your pump for 20 hours (2 rotations).

In winter you can drop that from 2 complete pool water rotations, to just one single full pool water rotation (10 hours in the above example). Therefor ideally during the in-between months, where it’s not freezing cold or super-hot, it would make sense to rotate the water in your pool 1.5 times per day (or for 15 hours per day in the above example).

Balance Your Pool Water

Before you begin the winterising process, it's essential to balance your pool water. This will help protect your pools surface and equipment during the winter months. If we eat too much salt, fat or sugar, our chemical levels can become unbalanced too, making us sick. Pool water is no different.

As a rough guide, you'll want to test and adjust the chemical levels in your pool water to the following ranges (your specific pool surface and environmental levels may impact these ranges):

• pH: Aim for a pH level between 7.2 and 7.6.
• Alkalinity: The ideal range is between 80 and 120 ppm (parts per million).
• Calcium Hardness: Aim for a range of 175 to 350 ppm.
• Chlorine: Ensure your free chlorine levels are between 1 and 3 ppm.
• Sunblock/Stabiliser/Cyanuric Acid: Not needed during winter.
• Add winterising chemicals (algaecide and phosphate remover).

A special note on Sunblock/Stabiliser/Cyanuric Acid:

Stabilizer is definitely not needed during winter. However, many pool owners are confused about what the chemical does, why you may or may not need it, and how much to use. During Summer, low amounts are beneficial to reduce total chlorine requirements and resulting chemical knock-on effect. Too much however will drastically reduce chlorine effectiveness. Read more here.

Start Clean

Before closing your pool for the winter, it's essential to give it a thorough clean too. This will significantly help in the prevention of algae growth, making it easier to reopen the pool in the spring.

Follow these steps to clean your pool:

Clean your pool thoroughly

• Remove any debris floating in the water or on the surface, using a pool skimmer.
• Brush the pool walls, floor, and steps to remove any algae or other build-up.
• Vacuum the pool floor to remove dirt, leaves, debris and other particles.
• Backwash sand/glass/DE media filters and clean cartridge filters, to ensure they’re functioning efficiently.

Protect Your Pool Equipment

It's essential to protect your pool equipment during the winter months. Follow these steps to ensure your equipment is ready for winter.

In Victoria’s suburbia it doesn’t typically get cold enough to freeze your pool water, so you shouldn’t have to worry about draining your equipment to protect against freezing.

One thing you will want to monitor though, is your chlorine levels if you have a non-probed chlorinator. A fully automated chlorinator will deliver exactly the chlorine you need, while a standard chlorinator will deliver the same amount every day, regardless of how much is actually needed. Meaning a standard chlorinator could easily over-chlorinate causing significant damage to equipment, pool covers and cleaners.

Conclusion

When winterising your swimming pool, there a re a few things to keep in mind.

• Consider an intermediate step between Summer and Winter modes.
• Clean the surfaces and your pool filters.
• Do a final chemical balance to set your pool up for success.
• Don’t just shut it down and forget about it for 6 months.
• Continue to empty baskets and run maintenance tasks, although likely much less often.
• Keep an eye on the condition of the water. It should stay crystal clear.
• Continue to monitor chemical levels. Mainly Chlorine/ORP and pH levels.

Then when it’s time to reopen for next season, it’ll be as easy as increasing your run times and a fresh chemical balance.