Dream Aquarium uses a modern validation system. Old or shared keys are quickly blacklisted, meaning even if a code works today, it will likely revert your aquarium back to the trial version within 24 hours.
Your serial number is encoded with your email address. If you use a leaked key and the developer flags it for excessive use, the license can be permanently canceled. The official policy states: "If a serial number becomes flagged as having been used on too many computers, we reserve the right to cancel that license and it will no longer work in future updates". Sharing or using stolen keys risks your paid license being revoked. dream aquarium screensaver serial number new