I agree Wayne, as long as there is sufficient water flow the heat will
dissipate. The problem comes about when a non-positive displacement
pump (doesn't push out all the water it pulls back in) gets enough back
pressure that the water in the impeller housing just recirculates. I'm
just cautioning that the canister filter may not be designed to lift
the water that far, but I don't know the model and therefore can't
research the maximum total head and resultant flow rate.

I would hate to hear of your pump burning up from excess
backpressure caused by the height differential and the filtration
combined (though some would argue this point since most cannister
filters use magnetic drive impellers and are thereby non positive
displacement pumps).

On Oct 27, 11:38 am, Wayne Sallee wrote:
The only way you could burn up such a pump, would be for
it to overheat, so as long as enough water is going
through it to keep it from overheating, it won't burn up.

Wayne Sallee
Wayne's Pets