Description
A Complete FROG Serene Floating Refill: 1 Mineral Plus 3 Bromine Cartridges
The FROG Serene Cartridge Kit refills a FROG Serene Floating System in one box. Inside are one blue mineral cartridge, good for 4 months, and three yellow 150 g bromine cartridges at about 2 to 4 weeks each.
Start a fresh mineral cycle and have your next two bromine swaps on hand. The kit ships free to US addresses on online orders at HotTubPirate.com.
Everything for a Fresh Serene Cycle
Drain, refill and start over with matching cartridges: a new 4-month blue mineral cartridge and the yellow bromine cartridges that go beside it in the floater.
Prefilled, Color-Coded and Ready
No scooping and no guessing. Set the blue cartridge to #6, the yellow one to your hot tub size, and snap both into the floater.
Spare Bromine Built In
Two extra yellow cartridges wait in the box, so when the first one empties you can swap right away and keep the bromine level steady.
Free US Shipping on Online Orders
The FROG Serene Cartridge Kit ships free within the US when you order online at HotTubPirate.com.
Key Features and Benefits
- 1 Blue Mineral Cartridge4 months of FROG minerals.
- 3 Yellow Bromine Cartridges150 g each, 2 to 4 weeks apiece.
- Serene Floating RefillFits the green Serene floater.
- Prefilled and Color-CodedNothing to measure.
- Up to 600 GallonsSettings matched to hot tub size.
- Lower BromineHolds 1.0–2.0 ppm with minerals.
- Free US ShippingOn online orders at HotTubPirate.com.
Product Details
| Product Detail | Information |
|---|---|
| Brand | FROG (King Technology, Inc.) |
| Product | FROG Serene Cartridge Kit |
| Kit Contents | 1 FROG Serene Mineral Cartridge (blue) and 3 FROG Serene Bromine Cartridges, 150 g (yellow) |
| Product Type | Replacement cartridge kit for FROG Serene Floating and In-Line systems |
| Made For | FROG Serene Floating System and FROG Serene In-Line System |
| Hot Tub Size | Up to 600 gallons |
| Bromine Cartridges | Yellow, 150 g (5.3 oz) each, EPA Reg. No. 53735-16 |
| Floating Holder Included | No |
| Estimated Supply | One 4-month mineral cycle plus three bromine changes (about 6 to 12 weeks of bromine) |
| Mineral Cartridge | Blue, 2.05 oz (58 g), silver chloride 0.5%, EPA Reg. No. 53735-11 |
| Mineral Setting and Life | #6, replace every 4 months or at each drain and refill |
| Bromine Active Ingredient | BCDMH (1-bromo-3-chloro-5,5-dimethylhydantoin) |
| Bromine Setting | 0 to 6, matched to hot tub gallons (200–600) |
| Bromine Cartridge Life | About 2 to 4 weeks each, replace when empty |
| Target Bromine Level | 1.0–2.0 ppm, at least 1.0 ppm at all times |
| Refillable | No |
| Recommended Shock | FROG Maintain non-chlorine shock, weekly or as needed |
| Hazard Classification (SDS) | Bromine: Danger, corrosive and oxidizer. Mineral: Caution, very toxic to aquatic life |
| Manufacturer Part Number | 01-14-3856 |
| Store SKU | 01-14-3856 |
| UPC | 722906038511 |
| Image Alt Text | FROG Serene Cartridge Kit box with one blue mineral cartridge and three yellow bromine cartridges |
How to Use the FROG Serene Cartridge Kit
- Balance the water first: Test with FROG Test Strips and adjust total alkalinity to 80–120 ppm, then pH to 7.2–7.6, then hardness to 150–250 ppm. Add one balancer at a time with the jets on and wait 6 hours before retesting.
- Start up with FROG Jump Start: After a fresh fill, set a starting level of 1.0–2.0 ppm with one Jump Start packet per 600 gallons. FROG says not to use a non-chlorine shock at start-up.
- Set both cartridges: Turn the blue mineral cartridge to #6. Turn the yellow bromine cartridge to the number on the setting chart for your hot tub's gallons.
- Snap them into the floater: Push both cartridges into the openings of the green FROG Serene Floating System holder until they stay in place, then let it float in the hot tub.
- Fine-tune for a week: Test daily for the first week and move the bromine cartridge up or down one number per day until the strip matches 1.0–2.0 ppm.
- Swap the yellow cartridge when empty: Replace it when it runs out, usually every 2 to 4 weeks. Drain the water out of the old one, then discard it or recycle it where available.
FROG Serene Bromine Cartridge Setting Chart
| Hot Tub Size | Bromine Cartridge Setting |
|---|---|
| 200 gallons | 0 |
| 250 gallons | 1 |
| 300 gallons | 1 |
| 350 gallons | 2 |
| 400 gallons | 3 |
| 450 gallons | 4 |
| 500 gallons | 5 |
| 550 gallons | 5 |
| 600 gallons | 6 |
From the FROG Serene Floating and In-Line manuals. The blue mineral cartridge always goes on #6. For the first week, test daily and move the bromine cartridge up or down one setting per day until the strip reads 1.0 to 2.0 ppm bromine.
Compatibility Notes
Before You Buy
- Made for the FROG Serene Floating System. The three yellow 150 g bromine cartridges snap into the green floater beside the blue mineral cartridge.
- Also works in a built-in FROG Serene In-Line holder. FROG's 2026 catalog lists the yellow 150 g bromine for both Serene systems. Owners who prefer the larger green 200 g bromine can choose the in-line kit, since either size fits both systems.
- Treats hot tubs up to 600 gallons. The mineral goes on #6 and the bromine on the setting chart number for your hot tub.
- Not for FROG @ease systems, which use SmartChlor chlorine cartridges.
- The floating holder is not included. This kit is cartridges only.
Which FROG Serene Cartridge Do I Need?
| Cartridge | Made For | Replace |
|---|---|---|
| FROG Serene Mineral Cartridge (blue) | Serene Floating and Serene In-Line | Every 4 months, or at each drain and refill |
| FROG Serene Bromine Cartridge, 150 g (yellow) | Serene Floating and Serene In-Line | When empty, about every 2 to 4 weeks |
| FROG Serene In-Line Bromine Cartridge, 200 g (green) | Mainly Serene In-Line (also fits Floating) | When empty, about every 2 to 4 weeks |
| FROG Serene Cartridge Kit (1 blue + 3 yellow) (this listing) | Serene Floating or In-Line refill | One mineral cycle plus three bromine changes |
| FROG Serene In-Line Refill (1 blue + 1 green) | Serene In-Line refill | One mineral cycle plus one bromine change |
| FROG @ease cartridges | FROG @ease systems only | Separate SmartChlor system, not interchangeable with Serene |
Colors help you tell them apart: blue is always the mineral, yellow is the 150 g bromine and green is the larger 200 g bromine, made mainly for in-line holders. Either bromine size fits both Serene systems.
Why Choose the FROG Serene Cartridge Kit
It bundles genuine FROG Serene cartridges in the ratio FROG packs them, so one order restarts your floater with fresh minerals and spare bromine. In-line owners can use it too, or pick the FROG Serene In-Line Cartridge Kit with green 200 g bromine for the larger cartridge size. Shop the full FROG Serene line, or browse all hot tub mineral cartridges at HotTubPirate.com.
Ideal For
- FROG Serene Floating System owners
- Starting a new 4-month cycle
- Drain-and-refill days
- Hot tubs up to 600 gallons
- Shoppers who want free shipping
Frequently Asked Questions
What comes in the FROG Serene Cartridge Kit?
One blue FROG Serene Mineral Cartridge and three yellow 150 g FROG Serene Bromine Cartridges. The floater is not part of the kit.
How long does the FROG Serene Cartridge Kit last?
The mineral lasts 4 months. The three bromine cartridges cover about 6 to 12 weeks at FROG's 2 to 4 weeks each, so many hot tubs add a bromine cartridge or two before the next mineral change.
Does the kit include the floating holder?
No. The kit is refills only. If you need the green floater, the FROG Serene Floating System includes it along with starter cartridges.
Will this kit work in my FROG Serene In-Line system?
Yes. FROG's 2026 catalog lists both the blue mineral and the yellow 150 g bromine for the In-Line System. The mineral goes on top in the holder and the bromine below it. The in-line kit with green 200 g cartridges is the other option.
Why does the kit have 3 bromine cartridges but only 1 mineral?
Bromine cartridges empty in 2 to 4 weeks, while the mineral lasts 4 months. The kit packs several bromine refills to keep pace with one mineral cartridge.
Can I use this kit in a FROG @ease floater?
No. The @ease floater is built around SmartChlor chlorine cartridges. Serene bromine and mineral cartridges belong in a FROG Serene floater.
Do I put both cartridges in at the same time?
Yes, at the start of a cycle. Set the blue mineral to #6 and one yellow bromine to your chart number, then push both into the floater. Keep the other two yellow cartridges for later.
When should I open a new kit?
At your 4-month mineral change or your next drain and refill, whichever comes first. That is when FROG says the blue mineral cartridge should be replaced.
What is the part number and UPC for the kit?
FROG's order code is 01-14-3856 and the kit UPC is 722906038511.
Is shipping included on the cartridge kit?
For US addresses, yes, when you order online at HotTubPirate.com. At $89.95 the kit is over our $50 free-shipping threshold.
How often should I shock while using the kit?
Weekly or as needed with FROG Maintain, a non-chlorine shock. Skip dichlor: FROG warns its cyanuric acid buildup makes the Serene bromine cartridge less effective.
What do I need at start-up besides the cartridges?
Balance the water, then add one FROG Jump Start packet per 600 gallons to reach 1.0 to 2.0 ppm before the cartridges go in, per FROG's floating manual.
How is this different from the kit with 4 bromine cartridges?
Both include one blue mineral cartridge. The other kit adds a fourth bromine cartridge, which helps busier hot tubs reach the 4-month mineral change without a separate order.
Can I buy the cartridges separately?
Yes. The blue mineral cartridge and the yellow 150 g bromine cartridge are each sold on their own, and the bromine also comes in 3, 6 and 12 packs.
Are the cartridges ready to use out of the box?
Yes. Every cartridge is prefilled. You only set the dials, mineral on #6 and bromine on your chart number, and snap them into the floater.
Safety Notes
Handle With Care
- The bromine cartridges are labeled Danger: corrosive, causing severe skin burns and eye damage. Wear gloves and eye protection when you handle or drain them.
- Do not open, break or refill the cartridge, and do not handle a damaged cartridge without protective gear.
- Strong oxidizer. Keep it away from heat, flames and combustible materials, and never mix it with other chemicals.
- Do not use it in a feeder or other device that has been used with calcium hypochlorite.
- The blue mineral cartridge carries a Caution signal word and is very toxic to aquatic life. Do not empty it into drains or ponds.
- Store all cartridges in their original packaging, tightly closed, in a cool, ventilated place (bromine at or below 86°F), locked up and away from children and pets.
Product Documents
Download the FROG Serene Floating System and In-Line System manuals for set-up and replacement steps, plus the official Safety Data Sheets for both cartridges in this kit.