FROG® Serene® Floating System (formerly SPA FROG)

Complete Hot Tub Sanitizing Floater creates Fresh Mineral Water

Average Rating: 4 43 Reviews

FROG Serene keeps your hot tub clean while eliminating the work and the guesswork. Instead of spooning in chlorine daily, you simply replace a pre-filled cartridge about once a month. FROG Serene works by killing bacteria in two ways with sanitizing minerals and a very low level of bromine. The resulting Fresh Mineral Water® has a completely different quality that provides the serene feeling you’re looking for.

Pool Foreground Hot Tub Foreground
50% Less

Lower your bromine use up to 50%* with FROG minerals

Bromine Disolves

Unlike chlorine, bromine slowly dissolves in hot water so it’s easier to regulate. Plus far less odors.

Self Regulates

Bromine is less impacted by pH swings ensuring sanitizing effectiveness

Soft Feeling

Soft feeling water that’s easier on skin, swimsuits and spa surfaces

Set and Forget

Just set it and forget it for weeks at a time

Money Back Guarantee

Money back guarantee

FROG Serene Family of Products

Video Introduction to FROG Serene Floating System


Additional Information

The FROG Serene Floating System Fresh Mineral Water hot tub system utilizes mineral and bromine cartridges designed to destroy bacteria, reduce bromine use by up to 50% and improve the overall quality of hot tub water. The minerals last up to four full months, while the bromine can be dialed in to meet your precise needs, usually about three weeks per cartridge. Just snap the two cartridges into the floating cap and relax!

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What size hot tub will FROG Serene work in?
Hot tubs 150 to 600 are perfect for FROG Serene.

How does FROG Serene compare to other bromine floaters or using chlorine?
If you are tired of smelly chlorine odors and having to spoon in chemicals every time you use your hot tub, SPA FROG is for you. FROG Serene is not just bromine. It contains FROG minerals that destroy bacteria so you need up to 50% less bromine. The result is soft water without bleached suits or smelly odors.

How long do the mineral and bromine cartridges last?
The mineral cartridge lasts four months or whenever the hot tub is drained and refilled. The bromine cartridge lasts 2-4 weeks.

Can I remove SPA FROG from the spa when in use?
Yes. Simply turn it upside down on any surface so the water fills the green holder and doesn’t make a mess. Just remember to replace it when you exit the tub.

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* Compared to the minimum ANSI recommended bromine or chlorine level of 2.0 ppm for a hot tub

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See Our Customer Reviews

  1. Dave Hoffman

    Rating: 3

    Like the minerals in the water but it takes time monitoring to keep the bromine at 1-2ppm. My tub is 300 gals and our water starts out at 8.4 with a alkalinity of 50 ppm. I like the effect of the minerals but stillHaving trouble getting the bromine level to stay at 1-2 ppm even on a 3 setting for my 300 gallon tub. On a 4 setting it only lasts 2-3 weeks and reads higher than 3-5 ppm.

    • Tom Sager


      Thank you for purchasing a Frog product for you spa! We are happy to assist you.

      First we need to make sure the water is balanced:

      Total Alkalinity: should be between 80 and 120 ppm. (by getting the Total Alkalinity in line first it will be much easier to balance the PH).
      PH: The PH needs to be between 7.2 and 7.8.
      Water Hardness: needs to be between 150-250 ppm.
      Wait 6 hours between adjustments. If balancing takes long than 2 days, add a chlorine shock to maintain sanitizer levels.

      I also suggest that you turn the setting down to 1 or 2 to achieve 1-2ppm on a consistent basis.

      Here is a link to our website that can also assist you in trouble shooting issues.

      Please let us know if you have any additional questions. We can be reached by phone @ 1-800-222-0169 M-F 8-5PM CST.

  2. Greg Schaefer

    Rating: 3

    Just replaced my 23 year old spa last summer. Somehow, I thought that the Frog In-line system would be easier to use. Seems to take almost the same amount of work and my readings (ph) seem to be all over the place. I will try again when I open up in spring, but if it isn’t better, I may just eliminate the mineral cartridge and use chlorine alone.I will re rate if I have better luck.

    • Tom Sager

      Hi Greg,

      If you experience any of the same issues this Spring when you re-open the spa, please give Dan or Allyn on our customer service team a call at 800-222-0169 and they will be more than happy to assist you. The Spa FROG System does help to buffer pH and sanitize the water, so you should not be seeing fluctuation of your levels.

      In the meantime, please let me know if you have any additional questions or concerns.

  3. Brian Lee

    Rating: 5

    Spa frog makes it easy — all you have to do is shock the spa once a week and use the dip strips to test your water. Not complicated at all. Thanks for coming up with a device so easy and so mild.

  4. Palma Jordan

    Rating: 5

    When we purchased the spa we used a different product the chemical levels were all over the place, the water was murky and it prevented us from enjoying it. Since using the FROG floating system our levels are kept consistent and the water is always crystal clear. I highly recommend all their products to keep your water clear and your family safe.

  5. Chuck

    Hoe best to convert a chlorine spa to Spa Frog. Drain and start over?

    • Tom Sager

      Hi Chuck,

      You are correct, you will need to drain your chlorine based water for the bromine based Spa FROG. Steps are as follows:
      1) Add new water
      2) Balance your water, use this infographic as a guide
      3) Use Jump Start, located in the Spa FROG package, to establish an initial residual of 1.0-2.0ppm of bromine
      4) Set your cartridges per instructions on packaging

      If you need further help look at the Spa FROG manual or call Dan & Allyn on our customer service team at 1-800-222-0169.

  6. Carter worthy

    What’s the difference between spa frog and @ease

    • Bryan Wall

      Hello Carter,

      Here is a short answer but please give me a call and we talk further. Spa FROG is a low level bromine water care system for hot tubs. FROG @ease is a self-regulating, low level chlorine water care system for hot tubs. Both work extremely well and make your tub care easy.

      Thank you,
      FROG Specialist

  7. William Sihler

    Your products have allowed me to keep PH level satisfactory with very little fuss. THANK you !


    Rating: 5


  9. cherylann sterling

    Rating: 5

    very easy to use!

  10. cherylann sterling

    Rating: 5

    Our first time trying Frog products, and it is very easy to use!

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