Bilinavy Spa in‑Filter Mineral Sticks for Hot Tubs, Blue 4‑Pack — Silver‑ion Cartridge Inserts, 4 Months Each

Bilinavy Spa in-filter mineral sticks are a 4-piece set of blue silver-ion mineral cartridges that sit inside your hot tub filter to help reduce impurities and refresh water for up to four months per stick.

These in-filter mineral sticks are made to work alongside your existing cartridge filter so you can enjoy clearer water with minimal fuss. Each box contains four blue sticks; every stick weighs about 10 oz and provides maintenance for approximately four months. They’re engineered for use in spas and hot tubs up to 500 gallons (about 2000 L) and require a minimum filter length and opening to fit correctly.

How do these mineral sticks improve my hot tub water?

The Bilinavy sticks release trace silver ions and other minerals that help control contaminants that make water appear cloudy or smell unpleasant. They don’t replace your sanitizer but act as a complementary treatment to keep the water feeling fresher between regular maintenance.

• Reduces suspended impurities that cause cloudiness
• Helps maintain a clearer, fresher-smelling hot tub environment
• Works continuously while the pump is running and the cartridge is in place

How long does each stick last and how many do I need?

Each Bilinavy mineral stick lasts up to four months under normal spa conditions. The 4-pack gives you roughly 16 months of coverage if you replace and rotate sticks as recommended, making it a cost-effective way to extend periods between more intensive treatments.

• Expected life: up to 4 months per stick
• Box includes 4 sticks for sequential replacement or for multiple tubs
• Low-maintenance option to reduce frequency of deeper cleanings

Will these fit my existing hot tub filter cartridge?

Fitment is simple but important: the mineral rods require a minimum filter length of about 6.5 inches and a minimum filter opening of 1-1/4 inches. They are designed to be placed inside standard cartridge filters and are suitable for tubs up to 500 gallons (2000 L).

• Minimum filter length required: ~6.5 inches
• Minimum filter hole diameter: 1-1/4 inches
• Suitable for spas and hot tubs up to 500 gallons / 2000 L

How easy is installation and ongoing use?

Installation is straightforward and does not require tools. Each pack includes a short manual with step-by-step instructions; the sticks are heat-resistant and designed to be inserted into the filter at the existing flow rate without modification.

• Quick install: place the rod inside the cartridge filter following the included manual
• Heat-resistant design to withstand normal spa temperatures
• No changes to plumbing or pump settings required

Who is this for: Bilinavy Spa in-filter mineral sticks are aimed at spa and hot tub owners who want a low-effort option to improve water clarity and freshness between regular sanitizing routines. They’re a fit for people with standard cartridge filters that meet the size requirements and for anyone managing spas up to 500 gallons who prefers extended-interval maintenance and reduced ongoing costs.