The SPA FROG In-Line System, with its patented design, is built right into the spa using the same replaceable mineral and bromine cartridges as the SPA FROG Floating System. Simply open the cap, pull up the holder and snap in the cartridges.
*Cartridge Only
Spa Frog In-Line System Bromine Cart is for the following models.
| Make | Model | Date Range |
| Caldera | Tahitian | 2009-2010 |
| Caldera | Niagara | 2009-Current |
| Caldera | Geneva | 2009-Current |
| Caldera | Cantabria | 2009-Current |
| Caldera | Hawaiian | 2009-2010 |
| Caldera | Kauai | 2009-2015 |
| Caldera | Moorea | 2009-2010 |
| Caldera | Salina | 2011-2015 |
| Caldera | Makena | 2013-2015 |
| Caldera | Martinique | 2009-2015 |
| Caldera | Palatino | 2010-Current |
| Caldera | Marino | 2010-Current |
| Caldera | Vanto | 2011-Current |
| Caldera | Aventine | 2010-Current |
| Caldera | Elation | 2009-2010 |
| Caldera | Tarino | 2013-Current |
| Caldera | C 30 | 2009 |
| Caldera | C 45 | 2009 |