are fluval M150 heaters submersable?

so, i bought (2) Fluval M150 heaters for my 55gal aquarium...

and there is a freakin line on it that says not to submerge below this point or something like that....

but i've read a couple times online that this is just something the canadian government made them put on there...

does anyone have experience with these heaters?
are they really fully submersable or not?

please help!

 

Amazon.com: Fluval M 150-Watt Submersible Heater: Pet Supplies

The line denotes the lowest water level not the highest.

 

actually it says DO NOT SUBMERGE BELOW WATER LINE.

 

I would follow the manufacturer's instructions to prevent warranty issues should a problem arise.

Personally, I prefer to keep the heater upright with the controller exposed. It allows for easier adjustment, and eliminates the possibility of a seal leaking and causing a short.

 

+1

 

it's gonna be almost impossible to do that. the rim on my tank makes them hang at an angle, and i'm worried they'll just fall in because fluval uses kinda like a bracket to hold the heater to the cups.