We know you're excited about your new hot tub.
But if you're new to hot tub ownership, it helps to understand the basics: filters, filtration systems, water care, and maintenance.
This beginner's guide explains how common filtration setups work and how to care for a removable cartridge filter. Always follow the owner's manual for your specific model.
Hot Tub Filtration Systems
A hot tub's pump moves water through its filter media, where the filter traps hair, oils, dirt, and other particles. Portable spas commonly use either a jet pump during programmed filtration cycles or a dedicated circulation pump. The exact schedule and controls vary by model.[1]
Jet-Pump Filtration
Some spas use the low speed of the primary jet pump to filter and heat the water during programmed cycles. Owners can adjust available filtration or heating schedules according to the manufacturer's instructions.[1]
Dedicated Circulation Pump
Other spas use a separate, lower-flow circulation pump for filtration and heating. Depending on the model, this pump may operate continuously or according to a programmed schedule. A dedicated filtration pump can operate more quietly and efficiently than using a larger jet pump for routine circulation.[1]
No-Bypass Filtration
No-bypass filtration is a design feature, not a separate type of pump system. In a no-bypass design, water moving through the system is routed through the filters instead of allowing some flow to return through the jets unfiltered. Availability and operation depend on the spa model.[2]
Hot Tub Filters
Most portable hot tubs use removable cartridge filters. Water passes through the filter medium, and the folds or channels capture particles that would otherwise remain in the tub.[3]
Pleated Cartridge Filters
Traditional cartridge filters commonly use pleated polyester or similar synthetic media wrapped around a supporting core. The pleats increase the available surface area for filtration. These filters must be rinsed, deep-cleaned, inspected, and eventually replaced.[3]
Specialty High-Flow Filters
Some manufacturers offer proprietary filters made with different synthetic media or channel designs. Their cleaning methods and replacement intervals can differ from standard pleated cartridges. For example, Hot Spring lists replacement intervals of two to three years for its polyester cartridges and four to six years for its TRI-X cartridges, depending on use and visible wear.[3]
Because materials and service lives vary, buy the filter specified for your model and follow its owner's manual rather than relying on a universal lifespan.
How to Clean Hot Tub Filters
Regular cleaning helps maintain water flow and reduces strain on the pump and heater. Cleaning frequency depends on usage, water conditions, and the manufacturer's instructions. Jacuzzi recommends a weekly rinse, monthly application of an approved chemical cleaner, and a deeper soak every three to four months for the filters covered by its guidance.[4]
The Quick Rinse
- Turn off power to the hot tub before removing the filter.
- Remove the filter according to the owner's manual.
- Use a garden hose at moderate pressure to spray between the pleats or channels and remove visible debris.
- Inspect the filter for cracks, tears, collapsed pleats, or persistent buildup.
- Allow the filter to dry completely if directed, then reinstall it before operating the spa.
Do not run the hot tub without a filter for an extended period. If you want to use the spa while one filter dries, a second compatible filter can be rotated into service.[4]
The Chemical Clean
Use only a product labeled for cleaning hot tub or spa filters. Do not use bleach, household cleaners, or dishwasher detergent, which can damage the filter or create water-quality problems.[4]
- Turn off the hot tub and remove the filter.
- Rinse away loose debris with a garden hose.
- Prepare the approved cleaner in a suitable container, following the product's dilution and safety instructions.
- Apply or soak for the amount of time stated on the cleaner label and in the spa manufacturer's guidance.
- Rinse the filter thoroughly so no cleaner remains.
- Allow it to dry completely if directed, inspect it, and reinstall it before restoring normal operation.
Filtration Is Only Part of Water Care
A filter removes particles, but it does not replace disinfection or balanced water chemistry. The CDC recommends routinely checking a residential hot tub's sanitizer concentration and pH. Its current guidance recommends a pH of 7.0–7.8 and at least 3 parts per million of free chlorine for hot tubs; owners should also follow the spa and chemical manufacturers' directions.[5]
Enjoy Your Tub
Now that you understand the basics of hot tub filtration and filter care, you can build a maintenance schedule around your specific spa, water conditions, and frequency of use.
Sources
The numbered citations in the guide link to the references below. Model-specific instructions in the owner's manual should take priority over general guidance.
- Bullfrog Spas. “Water Care Filtration & Heating Settings.” View source↑ Back
- Hot Spring Spas. “Better Water: 100% No-Bypass Filtration.” View source↑ Back
- Hot Spring Spas. “How Do Hot Tub Filters Work?” View source↑ Back
- Jacuzzi. “How to Clean Hot Tub Filter.” View source↑ Back
- Centers for Disease Control and Prevention. “Home Pool and Hot Tub Water Treatment and Testing.” View source↑ Back
Filtration schedules, filter materials, chemical products, sanitizer systems, and replacement intervals vary. Consult the owner's manual and a qualified spa professional when instructions conflict or equipment is damaged.