sponge filter advice

[skipper]

Hi everyone! I have a betta in a 20L with a nano sponge filter/usb nano pump. I plan to add some tankmates, betta permitting, in the future. I'd like to keep the nano and add another sponge filter, to avoid dead spots and since the current set up is cycled.  

I'm confused as to which size sponge filter to add. The nano and small sponge filters do not seem very different in my newbie eyes- where the nano is smaller, it seems to be so only by 0.25 to 0.75 of an inch. Taller/narrower vs shorter/squatter. Could someone kindly shed some light as to if/how/why these slight differences are important? I did watch the sponge filter video where Cory explained lift, does that play a role? 

Thank you!!

[GardenStateGoldfish]

In all honesty there really isn’t much difference, I think taller and slimmer is better unless you were trying to hide it, then shorter and fatter would be easier to hide. 

the reason I think tall and skinny is better is that I think it would be slightly better at mechanical filtration but really it’s like comparing a green and red apple or something like that. 

[skipper]

7 minutes ago, GardenStateGoldfish said:

In all honesty there really isn’t much difference, I think taller and slimmer is better unless you were trying to hide it, then shorter and fatter would be easier to hide. 

the reason I think tall and skinny is better is that I think it would be slightly better at mechanical filtration but really it’s like comparing a green and red apple or something like that. 

Thank you! I appreciate your confirming that I wasn't missing something important. I like the footprint of the nano, and also like for things to match. 

[DShelton]

The tubes snap together and the sponges can stack, if horizontal real estate in the tank  is limited. 

[skipper]

@DShelton Thanks for pointing that out! I will definitely keep that in mind and play around. I have more of a vertical real estate limitation in this particular tank (actual water is only about 9 inches deep), but will keep in mind for other tanks 🙂 Stacking would make cleaning a bit more efficient as well.