{"product_id":"aqualtra-spa-filter-prb35-in-compatible-5-x-9-drop-in-2-pack-washable-pet","title":"AQUALTRA Spa Filter PRB35-IN Compatible 5 x 9¼ Drop-In, 2-Pack Washable PET","description":"\u003cp\u003e\u003cstrong\u003eAQUALTRA's PRB35-IN replacement spa filter cartridge is a NSF-certified, washable 5\" x 9 1\/4\" drop-in filter designed to fit popular 35 sq. ft. hot tub filter housings and restore clear, comfortable water.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eThis two-pack of AQUALTRA spa filters is built to match the dimensions and openings of common PRB35-IN-style cartridges, delivering a direct replacement option that combines durable construction with effective mechanical filtration. The cartridges use a PET composite media and chlorine-resistant end caps to stand up to regular hot tub sanitizers while remaining BPA-free and NSF\/ANSI certified for material safety.\u003c\/p\u003e\n\n\u003ch3\u003eWill this filter physically fit my hot tub?\u003c\/h3\u003e\n\u003cp\u003eMeasure your existing cartridge to confirm compatibility: these AQUALTRA filters are 5 inches outer diameter and 9 1\/4 inches long, with 2 1\/8 inch top and bottom openings. They match many part numbers used by major manufacturers and are intended as drop-in replacements when the dimensions align.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eOuter diameter: 5\" (127 mm)\u003c\/li\u003e\n  \u003cli\u003eLength: 9 1\/4\" (235 mm)\u003c\/li\u003e\n  \u003cli\u003eTop \u0026amp; bottom opening: 2 1\/8\" (54 mm)\u003c\/li\u003e\n  \u003cli\u003eFiltration area: 35 sq. ft.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow well does it remove debris from spa water?\u003c\/h3\u003e\n\u003cp\u003eAQUALTRA cartridges use a PET composite element and a \"dirt-locking\" fabric structure that traps hair, leaves, sediment, and fine particles more effectively than ordinary pleated media. The construction helps keep floating and suspended contaminants out of circulation, improving clarity between deep cleans.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eEffective against hair, dust, sand, and leaves\u003c\/li\u003e\n  \u003cli\u003e35 sq. ft. media surface for increased dirt-holding\u003c\/li\u003e\n  \u003cli\u003eReduces frequency of heavy maintenance when used with routine cleaning\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eCan I clean and reuse these cartridges?\u003c\/h3\u003e\n\u003cp\u003eYes — the AQUALTRA PRB35-IN filters are designed to be rinsed and reused, which lowers replacement frequency and reduces waste. For best results, rinse every two weeks and remove the filter before soaking in any chemical cleaners to avoid corrosion of metal parts.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eWashable PET composite fabric for repeated use\u003c\/li\u003e\n  \u003cli\u003eRecommended rinse interval: about every 2 weeks\u003c\/li\u003e\n  \u003cli\u003eRemove filter from hot tub before backwashing or soaking\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eAre these filters safe with hot tub chemicals?\u003c\/h3\u003e\n\u003cp\u003eThe cartridge components — PET composite media, high-chlorine-resistant end caps, and polypropylene core — are selected to tolerate typical spa sanitizers and water care routines. The materials are BPA-free and tested against NSF\/ANSI standards for material safety; however, always follow your sanitizer manufacturer's guidance for chemical concentrations and exposure times.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eBPA-free materials and NSF\/ANSI certified components\u003c\/li\u003e\n  \u003cli\u003eChlorine-resistant end caps to extend service life\u003c\/li\u003e\n  \u003cli\u003eFollow chemical manufacturer recommendations to prolong filter life\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eWho is this for? This AQUALTRA two-pack is aimed at hot tub and spa owners who need a direct, reliable replacement for 35 sq. ft. drop-in cartridges — especially those with PRB35-IN-style housings or matching part numbers such as C-4335, FC-2385, Waterway 35, and Guardian 409-219. Choose this set if you want NSF-certified materials, washable media to cut down on replacements, and a close dimensional match for common aftermarket filter bays. Before purchasing, confirm your existing cartridge dimensions and compatibility to ensure a correct fit.\u003c\/p\u003e\n\u003csection class=\"product-faq-snippet\"\u003e\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Which hot tub models is this filter compatible with?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: It fits PRB35-IN style housings and many parts like C-4335, FC-2385, Waterway 35, and Guardian 409-219 when dimensions match.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: How often should I clean these filters?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Rinse the filter roughly every two weeks; more often with heavy use or visible debris.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"AQUALTRA","offers":[{"title":"Default Title","offer_id":56832169017684,"sku":"B0CGLT6L9R","price":72.92,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1063\/2652\/4244\/files\/aqualtra-front-packaging-filter-2-pack.jpg?v=1787024089","url":"https:\/\/gardenluxe.co.uk\/products\/aqualtra-spa-filter-prb35-in-compatible-5-x-9-drop-in-2-pack-washable-pet","provider":"Gardenluxe Uk","version":"1.0","type":"link"}