Sponge filter

[AmazonPassion]

I have a sponge filter in my main tank only used when I need to QT fish...Do I need it to be attached to an air pump for it to remain seeded or can I just unplug my air pump?

[RogueAgent94]

It would be better to attach an air pump to keep water circulating through the media. That would allow for all the bacteria to stay active in the sponge.

[AmazonPassion]

I sort of figured, how about if I placed the sponge filter directly below the spray wand?

[RogueAgent94]

It will stay 'alive' by just being in the tank. More bacteria will remain active with more flow. So if you put it in a higher flow spot then it'll be better .

[pirahnah3]

More flow thru the media (in this case the sponge) the more bacteria will for a to handle the nutrients.

[zombiecat03]

So is a sponge filter just hooked up to an incoming air supply?

[Magoo]

I've often wondered that too

[Matt B]

Most sponge filters have perforated tube inside the sponge to allow water through the sponge, there will also typically be a riser, either off to the side or in the center of the sponge with the air outlet located inside of it, as the air bubbles rise to the surface through the riser they create negative pressure thus drawing water through the sponge and perforated pipe. It then follows the air bubbles out of the top of the riser.

[Magoo]

Are they similar to airstones?

[Matt B]

In the sense that they are constantly releasing bubbles yes, imo the similarities end there. Thats all an airstone will do, make bubbles, the sponge filter will also serve as biological, and to a lesser degree, mechanical filtration along with the bubble aspect.

Imo, if I am going to have an air pump and tubing in there, may as well have the added benefits of an extra, seeded filter too.

[Magoo]

That sounds reasonable