Clean Spa Filters - in the Dishwasher?
Can you clean your spa filters in the dishwasher? I think the idea came about when cartridge manufacturers suggested that dishwasher detergent (not laundry detergent!) could be used as an alternative to TSP (trisodium phosphate) for soaking cartridges and removing greasy oil deposits before cleaning the filter.
My dishwasher hardly removes all of the tomato sauce it should, but it's a decent model. So I thought I'd put this to a test. Can you clean spa filters in the dishwasher? And perhaps more importantly: Should you?
The Dishwasher-Spa Filter Cleaning Test
My spa filters had not been cleaned in a month, which is my usual schedule, so I removed my filter cartridge. It's about 15" tall, so I was able to place it standing up on the lower rack of the dishwasher - it just barely fit. I added a small amount of dishwasher detergent to the reservoir, then set it on the longest cycle (115 mins) with a no-heat drying cycle.
The result? There was still debris stuck down in the pleats, even though it definitely looked a lot cleaner from the outside. I've seen some suggest laying the spa filter on the top rack of the dishwasher, so I repeated the test in this manner, even rotating the cartridge twice during the cycle. However, there was still small debris and discoloration deep in the pleats.
How to Clean Spa Filters
The tried and true method is still the best way to clean your spa filters. Hose the filter cartridge clean with a handheld garden hose nozzle. It's a wet and not particularly comfortable experience, but cleaning it pleat by pleat in an up and down motion does the best job. Here's a step by step guide for cleaning spa and hot tub filter cartridges:
- Turn off spa, open filter canister and remove cartridge.
- Spray carefully with a high pressure hose nozzle to remove debris from each pleat.
- Soak the cartridge for 8 hours in TSP solution (1 cup TSP per 5 gallons hot water). Rinse clean.
- Soak the cartridge 1 hour in an acid solution (1 cup acid per 1 gallon cool water). Rinse clean.
- Soak the cartridge again in the TSP solution for 10 minutes to neutralize remaining acids.
- To kill remaining microbes, allow filter to dry completely before reinstalling.
Steps 3 and 4 are not always necessary. TSP is great for removing oily deposits on spa filters. Muriatic acid (or dry acid) is used to remove mineral scale like calcium deposits. Be sure to wear proper protective gear when handling muriatic acid, and always add the acid to water (not water to acid).
Steps 3, 4 and 5 can be combined into one step when using our Spa Cartridge Filter Cleaner, which can remove both oils and minerals. We also have Leisure Time Filter Clean for an overnight soaking, or Leisure Time Cartridge Clean, which is a spray-on formula that works in minutes instead of hours.
A spray nozzle that works great for cleaning spa filters is the Filter Flosser. It can really get in there to clean between the pleats of your filter, even if the water pressure to your hose is not so great.
Final Tips
- DO NOT clean spa filters in the dishwasher! It's not very effective and could damage the filter.
- DO NOT clean spa filters with a pressure washer, for obvious reasons.
- Dry dishwasher soap is OK, but laundry detergent is NOT OK.
- Remember to rinse the filter thoroughly after soaking to remove all chemical traces.
- DO NOT use DE powder as a spa filter aid. However, Puri-Fiber or Aqua-Perl may be used if desired.
Conclusion
If you REALLY want to use your dishwasher to clean a hot tub filter, be my guest. But be warned: the dishwasher won't get your filter very clean. It shouldn't hurt the filter cartridge unless you use a heated dry cycle. You can use a small amount of dry dishwasher detergent as long as you remember to rinse the filter well once the dishwasher shuts off.