Winterize your pool:
How to perfectly protect your oasis
from frost & damage
When golden fall days come to an end
The golden September days are coming to an end and with them the pool season. While the last rays of sunshine are still dancing across the water, the most important autumn taskpreparing the pool so that it almost shines again in spring. The good news: with the right right strategy the winterizing a a relaxed weekend project.
New in the fall: Biodegradable overwintering agent, smart pool sensors for the ideal time and energy-saving methodsthat wallet and the environment protect it. Time to systemize the pool winterized and at the same time sustainability thinking.
The right moment: Winterizing begins at 15 degrees
Forget the calendar, your thermometer sets the tone. Only start when the water temperature is consistently below 15 degrees. Starting too early encourages algae growth, starting too late risks frost damage. In northern Germany this is usually mid-October, in the south often early November.
The water temperature is crucial. Above 15 degrees algae work at full speed, below 12 degrees their metabolism almost comes to a standstill. Your time window for perfect winterization is between 12 and 15 degrees. A digital pool thermometer is therefore a worthwhile purchase.
The first few nights of frost are particularly tricky. Water expands by ten percent when it freezes and can burst even stable PVC pipes. A forgotten pipe can quickly cause 500 euros worth of damage.
The crucial chemistry check: adjusting the water values correctly
The pH value is the foundation. If it is between 7.0 and 7.4, your pool will remain in balance. A value that is too low attacks metal parts, a value that is too high leads to limescale deposits. The correction only takes a few minutes and saves a lot of work in the spring.
This is followed by shock chlorination to 3 to 5 milligrams per liter. Together with a flocculant such as Jolly Gel, even the finest suspended particles are removed. The result is clear water that remains stable for months.
The last step is the winterizing agent. Bayrol Puripool Super 3 L from the Well Solutions store is particularly tried and tested. It reliably protects against algae, limescale and corrosion. The investment saves you a lot of chemicals and work in the spring.
Lowering the water level correctly: less is more
Empty the pool completely? A fatal mistake. Year after year, thousands pay a high price for this. The water in the pool is not ballast, but stability: it presses against the walls and liner. If this counter-pressure is missing, groundwater lifts the pool or the liner contracts irreparably.
The golden rule is: lower it, but lower it properly. The water level should be ten to fifteen centimetres below the inlet nozzles and the skimmer. For overflow channels, three to five centimetres below the edge is sufficient. This ensures that all installation parts at risk of frost are protected while the pool remains stable. It is clever to use the drained water for watering the garden, sustainably and free of charge.
The final protection comes after lowering: ice pressure pads from Bevo. These inconspicuous plastic cushions act like shock absorbers. Placed diagonally across the pool, they absorb the pressure of the freezing ice. Two or three are perfectly sufficient for a standard pool. Small helpers with a big effect.
Technical room in hibernation: where every detail counts
The pool pump is the heart of the system and is particularly sensitive to frost. Even a few drops of residual water can cause damage. For this reason, all pipes must be drained with compressed air. A compressor or a blow-out adapter makes the job easy.
The following applies to the filter system: set the multi-port valve to the winter position or between two positions, unscrew the pressure gauge and open the drain valves. Modern systems such as the Behncke Cristall² filter container Ø 400 mm have integrated winter positions and make winterizing easier. Sand filters lose about a third of their sand, cartridge filters are completely removed.
The heat pump is often forgotten, but with a replacement value of 800 to 3000 euros, it is the most expensive component. Here too, complete draining is mandatory, ideally with a cover. Accessories such as dosing floats, thermometers and pool robots are best stored dry in the cellar over the winter.
Covering philosophy: The final protective shield
A good winter cover, offered via the Well Solutions store, is like an insurance policy. Its benefits only become apparent in an emergency. Opaque models stop algae growth, even in mild winters. Water-permeable versions allow rain to run off and prevent dangerous water pockets.
The decisive factor is the fastening. Autumn storms of over 100 kilometers per hour are not uncommon. Tension straps at intervals of fifty centimeters, additional water bags on the edge or recessed fastening points ensure safety. If you skimp here, you run the risk of the cover flying off and having a lot of work to do in the spring.
A fine-mesh leaf net can be an alternative for those on a budget. It performs the basic function and costs only a third as much. In combination with ice pressure pads and regular checks, it is often sufficient for mild winters.
The cost check:
What really costs money
| Costs / Investment | Orientation area | Notes & factors |
|---|---|---|
| Winterizing agent | 30 – 50 € | Standard size, no special fabrics |
| pH agent & chlorine | 20 – 40 € | Depending on initial condition and quality |
| Ice pressure pad (one-off) | 40 – 80 € | Higher for larger pools or premium material |
| Working time (personal contribution) | 4 – 6 hours | Depending on experience and technical scope |
| Total costs (base case) | 100 – 180 € + purchases | With standard techniques and without additional costs |
| Possible damage / savings potential | Typical cost framework | Risk & Context |
|---|---|---|
| Basic cleaning after inadequate winterization | 800 – 1.500 € | For heavily soiled pools, algae, deposits |
| New pump after frost damage | 300 – 800 € | Depending on model and size |
| Cable repair | 200 – 500 € per meter | Especially for long distances or areas that are difficult to access |
| Algae control in spring | 100 – 200 € | If the water has been poorly pre-treated |
The calculation is clear: Even with premium products, winterization pays for itself several times over in the first year. A single forgotten valve can be more expensive than five years of careful preparation.
Spring anticipation: how to get the season off to a good start
After successful winterization, reopening is a walk in the park. At the beginning of May, 2 to 3 hours are usually enough for crystal-clear bathing water. Remove the cover, connect the technology, check the water values and you’re done. While others are still scrubbing for weeks, you can already enjoy your first dip in the cool water.
The psychological effect is priceless: If you were thorough in the fall, you start the new season relaxed. No guilty conscience at the first rays of sunshine, no hectic before the garden party. Your pool is ready when you are.
Checklist:
Your pool winter tasks at a glance
September:
- Check the water temperature daily
- Enjoy the last intensive use of the pool
- Check winter materials and buy more
October:
- Start when the water temperature is below 15°C
- pH value adjustment and shock chlorination
- Lowering the water level
- Empty and store technology
November:
- Add overwintering agent
- Placing ice pressure pads
- Fasten the cover so that it is storm-proof
- Schedule a monthly visual inspection
When exactly should I winterize my pool?
At a constant water temperature below 15°C, usually between mid-October and early November. The thermometer decides, not the calendar.
Can I do without overwintering agents?
Theoretically yes, practically no. The 30 to 50 euro investment will save you ten times as much work and chemicals in spring.
What happens if I empty the pool completely?
Disaster! Foil shrinks irreparably, groundwater can lift the pool, pool walls lose their stability. Never empty completely!
Do I have to look at the pool in winter?
Once a month is sufficient for a visual check. Also check the cover after storms.
How expensive will it be if I forget to winterize?
Expect to pay between 1000 and 3000 euros for repairs and basic cleaning. A single frozen pump costs more than five years of perfect winterization.
Can I winterize my saltwater pool in the same way?
Basically yes, but with special features: The salt electrolysis system must be switched off at temperatures below 15°C, otherwise it will be damaged. The cell is removed and stored in a dry place. Otherwise, the same steps apply as for the chlorine pool.
What do I do with the solar cover and pool robot?
Both are taken out of the water before winter. Clean the solar cover thoroughly, dry it and store it in a dark place, otherwise UV light will make it brittle. Empty the pool robot completely, clean the filter and store it in a frost-free place. A forgotten robot in the pool almost always means total damage.
Is a tarpaulin from the DIY store sufficient as a winter cover?
Maybe for one winter, but not in the long term. DIY store tarpaulins are rarely UV-resistant and tear in storms. A special pool cover for 200 to 400 euros will last five to eight years. A DIY store cover usually has to be replaced every year. At the end of the day, the cost clearly speaks for quality.
It is even better to plan a fixed pool cover when the pool is built. Brands such as grando, capena and novacomet offer solutions that not only protect in winter, but also provide comfort and safety in summer.