My betta is currently living in a 5 gal tank with a Whisper 10i filter linked below. This filter is kinda big in my opinion for this tank since the entire filter is submerge in water. Is there a smaller filter which would be better for a 5 gallon tank? The reason I want a smaller filter is because I want to divide the tank in half to house 2 betta, so I want to give it as much room as possible to swim around.
Whisper 10i
Whisper 10i