[green_valley]

Hi everyone,

I saw a lot of planted tank does not have those bubble oxygen. What really determines when the fish need them or not? I am planning to have 15 cardinal tetras in a 10G tank, and heavily planted.

Thanks.

 

[jedimasterben]

Those are typically only for show. If a tank has active filtration that breaks the surface of the water, some sort of aerator is usually always not required, especially in a planted tank, as the plants are actively using any dissolved CO2 and outputting O2.

With any type of fish other than a betta (they are "labyrinth" fish that breathe from the surface of the water), I would have active filtration via a HOB or canister filter, and this filtration will keep the tank well oxygenated for the fish.

 

[green_valley]

But I thought if it's only from the filter, it wouldn't enough.

 

[Kathyy]

It is the ripples that aerate the water, not bubbles. You can adjust your filter's outflow so it makes ripples on the water surface and not use an air stone.

Some people don't want ripples on the water surface and aerate the tank when plants aren't photosynthesizing when lights are off.