There are differences in circulation powerheads as well....those that are propeller type, can't mix air into the stream or drive undergravel filters, intank water polishing or mechanical or UV sterilizers...those that can use a venturi to add air, generally are bigger and louder, but can drive undergravel filters and intank devices like polishing or mechanical filters and UV sterilizers.
I have been told that circulating the suface of the water and water flow is a good idea and also with a powerhead you can add air (oxygen) as well. Just wondering how neccesary either of these are .
Agitating or moving the water surface helps to dislodge proteins, oils (fish food), dust and other debris and to promote gas exchange.
Depending on the placement of the devices, it can encourage a more even temperature throughout the aquarium.
I only use one device in my 72" long tank to help with moving the water surface. My canister filters in that tank use spray bars along the front and sides of the tank to accomplish water movement in the tank.
You may or may not need a device depending on the needs of your tank setup and fish you keep.
Agitating or moving the water surface helps to dislodge proteins, oils (fish food), dust and other debris and to promote gas exchange.
Depending on the placement of the devices, it can encourage a more even temperature throughout the aquarium.
I only use one device in my 72" long tank to help with moving the water surface. My canister filters in that tank use spray bars along the front and sides of the tank to accomplish water movement in the tank.
You may or may not need a device depending on the needs of your tank setup and fish you keep.
I'm partial to wave makers even in my planted tanks. I enjoy and imagine the fish enjoy varying currents. I don't use them on wave mode but they usually have a random setting, if I just need circulation I also prefer a wave maker, they have wide out puts, and they have many speed modes so you can dial it down or up to your preference. I use a few jebao wave makers which are incredibly cheap but have such awesome functions for the price point, mine are a couple years old and still going, I clean and lube regularly since the 1 year mark.
If you have ug filters you would like to rub they're definitely not your option
Powerheads direct current in a single, uniformed direction. They are mostly meant for filters (internal, overhead, canisters).
Wavemakers on the other hand creates waves as the name suggested. These are more spread out and create more water circulation in the tank.
I have seen powerhead attachments available which allows them to create waves as well. But IMO, i rather get a wavemaker since they are generally more "aesthetically appealing" when viewed in the tank.
Good thing about powerheads is, you most likely have one around. Personally I would use powerheads only for surface agitation and wavemaker for internal water circulation, though both can function either way.