ETH 300W External Thermal Aquarium Heater for 5/8" hose

I have two units plumbed in sequence. Very reliable, appears to be safe. There have been some power outages and the units seem unaffected.

Because it's outside of the aquarium, that's one less ugly equipment I have to look at inside the display tank.

Also, there's no way that my fish or anemones can get burned from touching it like an internal glass heater that goes inside your tank.

The instruction says it does have to be hung vertically to work.

Buy ETH 300W External Thermal Aquarium Heater for 5/8" hose Now