How Does This Filter Work!?

[BettaBubble]

So I bought a kit for my betta (I cycled it before I bought her) It said it can with an air pump and a filtration system. It doesn't have a hang on back filter. All it has is this large tube and on the bottom of the tube (the tube is more like a pipe) is the "filtration system". It's just a black plastic thing. Then I put gravel on the black plastic thing, and the air pump in the tube/pipe. I feel so stupid that I haven't questioned this system. How does this work? How does the nitrogen cycle work with this? My betta seems happy but I know that could be short lived. I have a 10 gallon with an already cycled filter and I could buy a bigger heater but unfortunately the betta is not at my house, but at my grandmas house. She thinks rectangular tanks are ugly and only wants round ones. I took everything to convince her to move her fancy goldfish from a 10 to a 55 gallon!

*she is NOT in a one gallon bowl! She is in a 3 gallon cylinder shaped tank.

 

[Aquaphobia]

Sounds like an under gravel filter. What happens is the air rising up the tube creates a vacuum behind it which pulls water down through the gravel into the plastic plate. Waste gets trapped there and your cycle bacteria grow on that.

 

[UglyAsian]

Seems to work.

 

[Chaory]

Yeah, it is a very poor filtration system, since it traps waste into the gravel, and underneath it. It's an old filtration system that isn't use much now and days. For a Betta, I recommend a sponge filter. HOBs can cause too much water flow for a Betta.

 

[Fish-whisper]

UG filters work the same as sponge filters, they would be a good choice for betta tanks that don't require strong current flow.