Here in Pasadena, California, pool maintenance is fairly unique because our winters are mild enough that you  do not  need to "close" or drain your pool as they do in the East Coast, Midwest, or other cold winter locations. However, because the pool remains open and exposed to the elements, it requires consistent (though reduced) care to prevent algae and equipment damage.

Here are the essential pool services for a Pasadena winter:

1.   Adjusted Filtration & Pumping

Since the water is colder, algae grows more slowly, allowing you to save on electricity due to reduced running time for the pool pumps.

• Reduce Pump Time:  You can typically cut your pump run time down to  4–6 hours per day  (compared to 8–12 in summer).³

• Freeze Protection:  Ensure your "Freeze Guard" is active.⁴  On the rare nights Pasadena dips below freezing, this sensor automatically turns on the pump to keep water moving, preventing pipes from cracking.

2. Chemical Balancing

The colder water in your pool changes the "saturation index" of your pool, which can lead to scaling or corrosion if ignored.

• Monitor pH and Alkalinity:  We get rain in winter in Pasadena.  Rainwater is acidic and can rapidly drop your pH, which eats away at pool plaster and other elements such as pipes, lines, filters, etc.
• Lower Chlorine Levels:  You will generally need significantly less chlorine in winter. Aim for  1–3 ppm. Many locals switch from automated chlorinators to simple liquid chlorine or a floating dispenser.
• Add Algaecide:  A "winterizing" algaecide treatment can provide an extra layer of protection if you plan to use the pool less frequently.

3. Debris Management (The "Windy" Season)

Pasadena is prone to Santa Ana winds and winter storms that dump leaves and organic debris into pools.  This is particularly true in green, leafy Pasadena, Altadena, La Canada, and surrounding areas.

• Frequent Skimming:  Organic matter (leaves, acorns) left at the bottom can permanently stain your pool's plaster or tile.
• Empty Baskets:  Check skimmer and pump baskets weekly.⁶  Heavy leaf fall can clog these, starving the pump of water and causing the motor to burn out.
• Filter Cleaning:  Winter is a great time for a "Filter Breakdown" (cleaning the DE grids or cartridges), as the system isn't under the heavy stress of summer.

4. Equipment & Cover Care

• Inspect the Heater:  If you plan on using the spa during the holidays, test the heater early in the season. Rodents often seek warmth in heater cabinets during winter and can chew through wiring.  Rats have been a significant problem recently in the area.
• Use a Pool Cover:  If you aren't swimming, a cover is the best way to prevent evaporation and keep debris out.⁷  If it rains, be sure to use a  cover pump  to remove standing water from the top of the cover so it doesn't collapse.⁸

Pro Tip for Pasadena Residents

If you have  solar heating panels  on your roof, ensure they are drained or bypassed during the coldest weeks (typically January) to prevent the small copper or plastic tubes from bursting during a frost.

Call us at Pasadena Pool Cleaning and Repairs with an wintertime pool maintenance issues or questions.  We can be reached at (626) 605-1956