Hi Trent,
Yes - you can deactivate the license on a computer by opening the "About ReefMaster" window (top button, main toolbar) and clicking Deactivate License. You can then reactivate on another computer using the existing license key.
If you do "lose" an activation (e.g. through a hard-drive failure) then just email us at This email address is being protected from spambots. You need JavaScript enabled to view it.
and we can free that activation again.
Matt