Though it is true that altogether the heater will likely use more energy, it does not run continuously. So it is apples to oranges.I guess a 20 watt filter is peanuts when you're sticking a 300 watt heater in the tank.
Not really apples and oranges. Power consumption is power consumption. Just because the filter doesn't operate continuously doesn't change the fact there is power being consumed, just at a less frequent amount of time and at lower levels than a continuously run filter.Though it is true that altogether the heater will likely use more energy, it does not run continuously. So it is apples to oranges.
"Effective" filtration is to subjective. So relating that to wattage is useless... kind of like apples and oranges.In terms of the most effective filtration per watt, a canister would be the best IMO given the amount of media they hold.
I still think comparing these two types in stock form, it's going to be hard to beat the general performance of a canister per watt consumed.When it comes to HOB power filters and canister filters, which uses the least amount of power, yet offers good performance.