Auto Top-Off (ATO) systems are designed to maintain a consistent water level in aquariums and similar setups by automatically adding water when the level drops. Most systems specifically replace evaporated water with fresh water (not salt), helping prevent salinity swings and reducing the need for manual daily top-offs. While ATOs sound simple, the quality of the sensing, the reliability of the pump, and the presence of safety safeguards determine whether the system will be accurate—or whether ... Read more »