yeah i read many reviews on the eheim series. i believe this one i bought after eheim was bought out or something so it isnt the old school nuke-proof heater but it still got good reviews on this forum and others too. the way i assembled the top was to silicone it up to the edge. any water that lands on top would fall off yes. i had an incident with my heater and turkey baster full of bloodworms and fall off the bloodworms did...onto my floor
but at least no water got through that i knew of.