Staff Answer
Sep 14, 2026 - 10:34 AM
According to this cell sizing guide, you cannot use an SJ-20 cell on an SJ-45. The SJ-45 is designed to operate with the SJ-45 replacement cell, while the SJ-20 cell is specifically intended for the SJ-20 system.
It is also not typically recommended to "downsize" a salt cell. Doing so will require the cell to work at a higher output and/or run for more hours to do the job, which typically translates to the cell becoming depleted more quickly. For example, it would be more ideal for a SJ-45 cell to run less hours to create the same amount of chlorine as a SJ-20 running for more hours. In the long run, this typically is a much more beneficial scenario than the relatively small cost savings that you would get upfront from buying a smaller cell. Additionally, consider the extra capability that you have on hand with a larger cell - if a pool problem ever arises, the SJ-45 would allow you to create on demand more chlorine, more quickly. That means you may be able to take care of any such issue quickly and prevent it from becoming a larger problem such as an algae bloom.
Take a look at this helpful video that talks about the issue: https://www.youtube.com/watch?v=R4wGu...
Please let us know what other questions you might have.
Add New Comment