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ICS-STPK Replacement Water Filters for ICS-STP System


ICS-STPK Cartridge Filter Replacement Kit

The ICS-STPK cartridge filter replacement kit is designed specifically for the Cascadian ICS-STP water treatment system and is perfect for every use in whole home or business. It is an excellent choice for city or well water. 

Contains Two Filters:

Filter One:

The first filter is a high capacity multimicron depth sediment filter. This filter removes particles down to 5 micron to clarify the water and protect downstream treatment and the plumbing, fixtures and appliances.

Filter Two:

The second filter is a top quality activated carbon filter combined with Cascadian PolyHalt®. It is specially designed to reduce the total number of filters required for maximum treatment without increasing the overall size of the treatment system.

Water is first treated by passing through the activated carbon component to reduce chlorine, improve taste and odor, and reduce volatile organic compounds (VOC's).

After carbon treatment the water passes through PolyHalt® media where it is softened without salt and further conditioned to treat silica and blue copper staining which extends the life of plumbing, fixtures, appliances, windows and glassware etc., by protecting them from damage caused by untreated water.

    A Commitment to Eco-Friendliness

    Our ICS-SPK filter replacement kit is as kind to the environment as it is to your water. It's a no water waste solution, ensuring that every drop counts. Plus, it's legal everywhere – even in places where salt softeners are banned​​.

    Simple Maintenance

    With the Cascadian ICS-STPK cartridge filter replacement kit, maintenance is a breeze. You'll only need to change filters once a year or more as required. Enjoy hassle-free, easy maintenance that keeps your water at its best without the stress​​.

    Convenient Filter Subscription

    Kickstart your journey to better water with our convenient filter subscriptions. Purchase your first replacement filters a year after setting up your system and select the subscription option to save time and 10% off and get free shipping. Enjoy continuous clean water without the need for constant reordering​.

    Ready to transform your water experience? Purchase your Cascadian ICS-STPK cartridge filter replacement kit today!

    See product specifications below for more details

          Other Specs

          Filter Size: 4.5" x 20"

          Connection: 1" FNPT

          Treatment Included: S, Sediment T, Taste & Odor K, Replacement Kit

          • Eco Friendly

            No Water Waste

          • Legal Everywhere

            Our filters can be used where salt softeners are banned

          • Easy Maintenance

            Change filters once or more per year

          • 60 Day Guarantee

            Return it, no questions asked

          Frequently Asked Questions

          Where does the ICS system go in my home?

          Where it can fit, and where it can easily get access to your home's water source. This is typically a garage, crawlspace, or even a closet. If you have questions a plumber would be able to help you find the best spot. During maintenance you'll need to fit a bucket and have enough space to turn the sump wrench which comes with your system

          How often do I replace the filters?

          Most people replace their filters once per year, or sooner if they start seeing issues with their water again. Learn about water issues here

          What is the return policy?

          If you are unsatisfied within 60 days of purchase, return the housing and we'll refund your purchase no questions asked.

          How fast do you ship?

          We typically ship same business day if the order is placed before 2 pm PST using UPS ground.

          Rely on our expertise to deliver the simplest water treatment

          Customer Reviews

          Based on 40 reviews

          Price is ridiculous

          Hi Gary, Thanks for your concern over price. We do offer an annual subscription service where you can save 10% on filters. If you would like to subscribe we'll be happy to help!

          A Rudenko (Coupeville, US)
          Not so easy to replace filters

          This was my first year in a house with a Cascadian system. Replacing the filters made an immediate difference in water quality. Mine needed to be changed after about 10 months; at that point I was smelling chlorine and some other off odors. It cost close to $200 to hire a plumber to change the filters, and even for him it wasn't a piece of cake. So between the filters and the plumber, plan on spending about $700 a year. Be aware that the Cascadian system does not remove PFAS from your water, if that is a problem in your area. I installed an additional Zerowater filtration system for my drinking water to take care of that problem.

          Ordering the replacement filters from Cascadian was fast and easy, and they arrived in a couple of days. Very nice service on the phone as well.

          Hi A Rudenko, Thank you for your thoughtful review! We're thrilled to hear the filters made an immediate difference in your water quality. We understand replacing filters can be daunting, especially the first time. We'd like to offer an alternative for future changes: DIY!

          Many customers find changing Cascadian filters themselves to be a breeze. We have a comprehensive video guide that walks you through the process step-by-step: [link to video It's quick, easy, and can save you hundreds.

          Of course, if you prefer professional assistance, we completely understand. We're happy to recommend a trusted plumber in your area.

          As for PFAS, you're right - our system doesn't currently address this emerging contaminant. We appreciate you bringing this to our attention and are actively exploring solutions.

          Thank you again for your feedback. We're always working to improve your Cascadian experience, and your insights are valuable.
          Sincerely, The Cascadian Team

          David Farrell (Ranchos de Taos, US)
          Great system!

          We no longer have to use a pitcher to filter our drinking water, our coffee tastes better, our showers are not soapy-feeling, our clothes are cleaner in the washer, and our dishwasher is doing a much better job!
          Installation was fairly easy, and I did not have any issues.

          Dear David Farrell,

          Thank you so much for your wonderful 5-star review of the ICS-STP PolyHalt® Water Softener with Taste/Sediment Filters! We're thrilled to hear that the system has significantly improved your daily water usage, enhancing everything from your drinking water to laundry. It's great to know that your coffee tastes better, showers feel more refreshing, and your appliances are performing more efficiently. Also, hearing that the installation process was straightforward and hassle-free is fantastic feedback. Your satisfaction is our top priority, and we're delighted to have met your expectations. If you need any further assistance or have more insights to share, please don't hesitate to reach out.

          Warm regards,
          Cascadian Water Customer Service Team