Hot tub and spa cartridges do some real heavy lifting. Pounded non-stop by water, filling up with dirt, keeping your spa water clean and clear.
But ~ they don’t last forever. To prevent dirty water and disease, spa filters should be replaced every 12-24 months. 12 months, if the hot tub is heavily used by several people, or 24 months for a spa that may be used weekly, by just a few persons.
You can set a scheduled reminder to replace your filter cartridge every certain number of months – or use these tips below to determine when your spa filter has reached a point of no return.
Here we go!
1. Filter Pressure
A new spa filter cartridge of good size should last a month or so before it needs to be removed and cleaned. After cleaning, you should notice that the filter pressure has dropped (if your spa filter has a pressure gauge), and flow rate has increased. If the pressure doesn’t drop back to the original pressure, or if it only drops for a few days or weeks, it’s probably time for a new spa filter cartridge. And, if the pressure never seems to rise – that also means that your cartridge is not trapping dirt like it should. Using a spa filter cleaner chemical, can improve flow rate and reduce pressure, as it removes oils and minerals that clog up a spa filter.
2. Water Clarity
Probably the most definitive test of your spa filter – does it keep the water clear and clean? A new cartridge should be able to give you sparkling water, as long as you are using sanitizer and running the filter for long enough each day. Over time, fibers in the filter loosen, and allow small particles to pass through, back into the spa. Turn on the spa light to get a good look at the water. Is there lots of tiny, floating stuff? Does the water look gray and lifeless, or does it reflect light and sparkle? If you pay attention to these things, you should begin to notice when water clarity changes. If cleaning your spa filter doesn’t help – it’s time for a new spa filter.
3. Sanitizer Consumption
Whether you use bromine, chlorine or alternative sanitizers, when the filter is not working like it should, more sanitizer can take up the slack. It will take more sanitizer to reach the same test readings and more shocking of the spa, to keep water clean. If you begin to wonder why you have to use more sanitizer, and begin to question the potency of your purchase – you may instead be looking at a spa filter problem – not a sanitizer problem. When you have to use more chemicals to keep the water clear, and more adjustment chemicals to balance the water chemistry, it’s time for a new spa filter.
4. Damage to Cartridge
Spa filter cartridges can be damaged by poor water chemistry, or very high sanitizer levels, although this type of damage can be hard to see clearly. Other types of damage is easy to spot, like cracked end caps, broken bands, or pleats that are uneven and no longer straight. Cleaning your spa cartridge with a pressure washer, or taking it to the car wash, as I have heard some people do – is not recommended. The fragile filter fabric can develop small holes, or large tears, if it is cleaned too aggressively. If you have a spare spa filter, keep it stored indoors. Sun and snow can damage a spa filter cartridge left out in the open – time for a new spa filter.
5. Number of Cleanings
They say that each time you clean a spa filter cartridge, a little bit of it’s filtering ability is lost. This is because the cleaning process lifts and separates the layers of fibers that trap dirt. Cleaning with water pressure opens up the layers, and makes it easier for dirt to pass through unfiltered. After 10-15 cleanings, your spa filter cartridge may have only half of the dirt capacity that it had when new, which means more sanitizer and more filter run time is required to keep the water clean. Whether you wait 18 months, or 12 cleaning cycles, eventually it’s time – for a new spa filter!
Don’t wait until it’s too late, and you begin to overspend on pump energy and chemical cost – replace your spa filter on a schedule, and your spa water will always look great!
Hot Tub Works